Battery Monitoring Systems
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- VIGILANT®
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- BDS-Pro
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- VGM-100
- ELM-Series
Next Generation Battery Monitoring System
The ground-breaking VIGILANT® Battery Monitoring System (BMS) with Advanced Multi-Function (AMF) sensors employs several new battery parameters to predict battery condition. Included in these critical parameters are Battery Cell Condition, Battery State of Health, and Battery (at) Risk Factor. These new features are made possible by machine learning algorithms built into the VIGILANT®.
The following key battery parameters are monitored and recorded by the VIGILANT®: string voltage, float current, cell voltage, cell resistance, terminal & connection resistance, cell & ambient temperature, dc ground fault, and electrolyte level.
Web-Based, Remote Battery Monitoring
- A key advantage of the VIGILANT® is how it processes measurement data
- Rather than simply read and display measured parameters, the VIGILANT® also uses Artificial Intelligence to calculate the state of health (SoH) of the battery
- Measurement data and analysis is done via a built-in web-server, which can be accessed with any browser
- The web-based software eliminates the need for a standalone software package and is viewable on a desktop or mobile environment
Predicting Battery Condition
The VIGILANT® utilizes several technologies new to the battery monitoring industry to predict battery failure:
- Battery Cell Condition: Using machine learning algorithms to accurately calculate deterioration much earlier than current Ohmic testing methods
- Battery State of Health: Algorithms encompassing 12 key parameters to estimate the health of the battery as a whole. It includes measured changes in internal & external factors and in all parameters that could identify a potential reduction in anticipated battery life
- Battery Risk Factor (RF): Employing individual cell SoH along with temperature and ripple current to better predict risk of battery failures
- True Float Current: VIGILANT’s® Advanced Multi-Function (AMF) sensors measure true float current without the remanence and temperature problems of Hall-effect transducers
Key Features
- One-click reporting: Quickly create reports with a single click from the web-interface.
- Built in web-interface: Data is recorded and stored on the VIGILANT® monitor, eliminating the need for a 24/7 network connection.
- Unobtrusive: System does not affect battery performance in any way.
- Battery alarming: Alarm against user-defined battery thresholds, available via Modbus and dry contacts.
- Watchdog alarming: Dedicate watchdog circuit will restart the CPU upon hangup with a secondary circuit for alarming.
- Fleet management software: Aggregate a fleet of systems in a single interface with a bird’s eye view of systems in alarm.
Measured Parameters
- Float voltage
- Float, charge, & discharge current
- Cell/unit voltage
- Cell/unit resistance (mΩ)
- Interconnection resistance (μΩ)
- Cell/unit temperature
- Electrolyte level
- Ground fault status
- Ripple voltage
Specifications
Working Voltage | 0.05 – 18.5VDC |
Voltage Resolution | ± 1mV |
Post Temperature Resolution | ± 1ºC |
Cell Resistance Resolution | ± 7μΩ |
Strap Resistance Resolution | At 100μΩ strap r: ± 2μΩ |
Float Current Resolution | At 100μΩ strap r: ± 1mA |
Charge/Discharge Current | Max 800μΩ strap r: ± 0.1% Max 400μΩ strap r: ± 0.1% Range: 2,000A |
Electrical Supply (from DC supply) | 36 – 72VDC, 90 – 300VDC, 280 – 580VDC |
Other Power Options | 24V mains supply |
System Internal Power | via comms system |
Operating Power (from charger) | @ 60 cells: 25W |
Operating Temp Range | -4 – 70 ºC (25 – 158ºF) |
Isolation I/P to O/P | 1000VDC |
Test current @ 2.5V | 20A |
Onboard Storage | SSD |
Memory Capacity | 20 years of battery data average, expandable for larger systems |
Local Data Download | Via USB port |
External Protocols | Modbus TCP/IP, DNP3 (in development) |
Network Interface | RJ45 Ethernet |
Dimensions (L x W x H) | Sensor: 50 x 50 x 25 mm (2 x 2 x 1 in.) Monitor: 242 x 200 x 65 mm (9.5 x 8 x 2.6 in) |
Resources & Support
Product Literature
Support Documents
Video Resources
FAQs
What battery parameters does the VIGILANT® monitor?
The VIGILANT® monitors the following parameters and records them at the specified interval:
- Float voltage
- Float current
- Charge & discharge current
- Ambient temperature
- Cell/unit voltage
- Cell/unit resistance
- Interconnection resistance
- Terminal resistance
- Negative post temperature (per every cell/unit)
- Electrolyte level
- Ground fault
How does the VIGILANT® meet NERC PRC-005-6 compliance?
See the Battery Monitoring for NERC Compliance page. This page outlines how the VIGILANT® meets each attribute of NERC PRC-005-6.
Does the VIGILANT® meet NERC TPL-001-5 compliance?
Yes, see the Battery Monitoring for NERC Compliance page. This page outlines how the VIGILANT® meets each attribute of NERC TPL-001-5.
Is the VIGILANT® compatible with all battery types?
The VIGILANT® is designed to work with most stationary battery types, including VLA/flooded, VRLA/sealed, and Ni-Cad batteries. The exception is Lithium-Ion, which the Vigilant is not compatible with.
Does the VIGILANT® tell me if a battery is bad and/or what the remaining life is?
While the VIGILANT® can provide an overall idea of battery health, it does not explicitly state whether a battery is bad or not. The system will provide many parameters necessary to allow the end user to make a judgement call on whether or not a battery should be replaced. A future update will provide functionality to estimate the remaining life of a battery using machine learning algorithms.
The VIGILANT® monitors the following parameters and records them at the specified interval:
Float voltage
Float current
Charge & discharge current
Ambient temperature
Cell/unit voltage
Cell/unit resistance
Interconnection resistance
Terminal resistance
Negative post temperature (per every cell/unit)
Electrolyte level
Ground fault
See the Battery Monitoring for NERC Compliance page. This page outlines how the VIGILANT® meets each attribute of NERC PRC-005-6.
Yes, see the Battery Monitoring for NERC Compliance page. This page outlines how the VIGILANT® meets each attribute of NERC TPL-001-5.
The VIGILANT® is designed to work with most stationary battery types, including VLA/flooded, VRLA/sealed, and Ni-Cad batteries. The exception is Lithium-Ion, which the Vigilant is not compatible with.
While the VIGILANT® can provide an overall idea of battery health, it does not explicitly state whether a battery is bad or not. The system will provide many parameters necessary to allow the end user to make a judgement call on whether or not a battery should be replaced. A future update will provide functionality to estimate the remaining life of a battery using machine learning algorithms.
Installation & Service FAQs
Does Eagle Eye offer installation of the VIGILANT®?
Installation & commissioning of the VIGILANT® system is required to be performed through Eagle Eye Services or a certified third-party contractor.
Can the end-user install the VIGILANT® system?
At this time we discourage installation of the VIGILANT® system by the end-user. The system requires specific tools and training in order to be successful. Installation options can be discussed with a salesperson or your service contact.
How long does it take to install a VIGILANT® system?
Installation time can vary depending on a number of factors such as battery size, battery type, site conditions, etc. The typical 60-cell battery system can be installed in 10-16 hours by a certified installer.
Can the VIGILANT® be installed while the battery is online/in-service?
It depends on the battery type, or more specifically how exposed the battery posts are on the system. The VIGILANT® has 2 main connection types to the battery which determine if the installation can occur with the battery in service:
- Clamp Connections: If the battery has an exposed square post, the VIGILANT® can be installed by connecting steel clamps to each battery post. The clamp is fixed to the post with 2 screws that do not interfere with the battery. These posts are typically seen on VLA/flooded batteries, but also some VRLA/sealed designs.
- Tab Washer Connections: If the post is recessed, covered, or otherwise not accessible then a tab washer is typically used for connection. Installation of tab washers requires the system to be taken offline for 30-40 min. This is typically seen on most VRLA/sealed, front facing, and OPzS battery designs.
Are all installation components included with the VIGILANT®?
The system as shipped includes all core components of the system: the monitor, sensors, connection hardware, and wiring harnesses. Additional wiring specific to the site will be provided by the installer at time of installation. This includes power cabling, longer sense leads for jumpers, and longer comms cabling between sensors. The system does not include Ethernet between the monitor and the network.
How is the VIGILANT® wired to the battery, or is it wireless?
Every cell/unit on the battery system is assigned a single VIGILANT® sensor. That sensor is wired directly to the battery connections with as short of wire as possible. All sensors are connected in a loop via RJ12 comms cable back to the monitor. This allows the sensors to be powered from the monitor while greatly reducing the amount of sensing cables required. Eagle Eye Power Solutions has past provided systems with longer cable runs as well as wireless technologies and found that both are subject to noise from the environment, decreasing the reliability of the system overall.
Installation & commissioning of the VIGILANT® system is required to be performed through Eagle Eye Services or a certified third-party contractor.
At this time we discourage installation of the VIGILANT® system by the end-user. The system requires specific tools and training in order to be successful. Installation options can be discussed with a salesperson or your service contact.
Installation time can vary depending on a number of factors such as battery size, battery type, site conditions, etc. The typical 60-cell battery system can be installed in 10-16 hours by a certified installer.
It depends on the battery type, or more specifically how exposed the battery posts are on the system. The VIGILANT® has 2 main connection types to the battery which determine if the installation can occur with the battery in service:
Clamp Connections: If the battery has an exposed square post, the VIGILANT® can be installed by connecting steel clamps to each battery post. The clamp is fixed to the post with 2 screws that do not interfere with the battery. These posts are typically seen on VLA/flooded batteries, but also some VRLA/sealed designs.
Tab Washer Connections: If the post is recessed, covered, or otherwise not accessible then a tab washer is typically used for connection. Installation of tab washers requires the system to be taken offline for 30-40 min. This is typically seen on most VRLA/sealed, front facing, and OPzS battery designs.
The system as shipped includes all core components of the system: the monitor, sensors, connection hardware, and wiring harnesses. Additional wiring specific to the site will be provided by the installer at time of installation. This includes power cabling, longer sense leads for jumpers, and longer comms cabling between sensors. The system does not include Ethernet between the monitor and the network.
Every cell/unit on the battery system is assigned a single Vigilant sensor. That sensor is wired directly to the battery connections with as short of wire as possible. All sensors are connected in a loop via RJ12 comms cable back to the monitor. This allows the sensors to be powered from the monitor while greatly reducing the amount of sensing cables required. Eagle Eye Power Solutions has past provided systems with longer cable runs as well as wireless technologies and found that both are subject to noise from the environment, decreasing the reliability of the system overall.
Software & Communication FAQs
What software does the VIGILANT® require?
At a minimum, an up-to-date web-browser is required to login and view the web-interface. This can be done on most devices such as smart phones, tablets, laptops, and desktop computers.
No additional software is required to use the system; however a Fleet Management Software is available for monitoring a large number of systems on a single network.
How does the VIGILANT® store data?
All measured data is stored on an SSD in each individual VIGILANT® Monitor. The SSD is sized to accommodate 20 years of measured battery data. A permanent connection to the monitor is not required for the system to measure and record data.
How are updates handled?
Update files are available on the Eagle Eye Power Solutions website (see Help Center) and uploaded on the monitor by the end-user. They can be installed over network of via direct connection to the unit. Eagle Eye Power Solutions also offers a service to perform updates if requested.
A newsletter will be released as new updates are available.
How does the VIGILANT® communicate?
The VIGILANT® has a built-in web server with a dedicated IP address (default is 192.168.1.250). The web server can be accessed on a web browser from any PC on the same network via the monitor IP address. The IP address can be set to DHCP or a static. An internet connection is not required, nor are there any cloud based features on the system.
What interface/connection options does the VIGILANT® have?
The VIGILANT® system has an Ethernet port for connection to a network or direct connection to a computer. Both access the web-interface and Modbus communication can occur simultaneously over this port.
For hard-wired alarming, the system has (2) dry contact relays.
What ports are needed for network communication?
Port 80 is the primary port for communication and control of the VIGILANT® monitor. If using Modbus port 502 and 0502 are needed.
What protocols are supported by the VIGILANT®? What common protocols are not supported?
Currently Modbus TCP is the only external protocol supported. DNP3 protocol is in development for release in 2023.
The following protocols are not supported: SSH, HTTPS, Telnet, and SNMP.
Does the VIGILANT® have system logs?
System logs are accessible by Eagle Eye Services only and are used for troubleshooting device failure. Customer accessible system logs may be provided in a future update.
What data can be downloaded from the BMS?
All collected data residing on the VIGILANT® monitor/manager web-server may be accessed via internal networks (if the battery is on-site or available to those networks, – such as remote sites coupled to the company net by wireless or land-line). The system appears as a web site, and can be accessed and navigated as such. If the system is accessed via the internet, again it will be accessible by use of a URL exactly the same as any website.
All data will remain in the VIGILANT® memory for the life of the SSD memory (see the Vigilant Expert data sheet). Download of the data to a company database can be achieved at any time by CSV files, Modbus or DNP3 (2023 release).
How does the VIGILANT® comply with our cyber-security requirements?
When they were introduced over 30 years ago, Battery Monitoring Systems were stand alone systems and seldom integrated into an organizations control and reporting network. With the increase in remote monitoring and the increasing risk of cyber attacks that is no longer practical.
For example, the NERC CIP-003 Standard requires that all electronic access to communicable products that are located within an Electronic Security Perimeter such as a substation. Must have access to these devices controlled by the Responsible Entity which effectively makes a battery monitor an intelligent sensor. Because the Vigilant Monitoring System does the basic alarm analysis within the controller it is ideal for this application as it does not require a secondary device to analyze and distribute the collected data, as the previous generations of monitor do.
What type of alarming does the VIGILANT® have?
The VIGILANT® has several means of alarming based on the measured parameters:
- Monitor alarm relay: There is a single dry contact relay available for when a critical alarm occurs.
- Modbus point: There is a Modbus point available for when either a warning or critical battery alarm occurs.
- LEDs: There are LEDs on the front of the monitor that correspond to various alarms on the system.
- Web-interface: All alarms are viewable on the VIGILANT® web-interface.
- Fleet Management Software (optional): Critical and warning alarms are viewable for all installed systems.
Additional alarming paths are in development, including DNP3.
Does the VIGILANT® perform self-checks?
The VIGILANT® system performs many self-checks on the system sensors and the monitor itself as part of its program. Alarming is available for the following failure modes:
- CPU failure/lockup
- Loss of power
- Loss of communication to sensor bus
- Failed or disconnected sensor
What dry contacts are available for alarming?
The VIGILANT® monitor includes 2 dry contacts standard:
- Battery alarm: Occurs when any measured parameter reaches critical alarm level.
- Watchdog alarm: Occurs when any of the 4 watchdog parameters occur (see above FAQ)
What are the dry contact ratings?
The maximum power rating of the contacts is 300 watts, not to be exceeded. If the breaking voltage is 300V then the breaking capacity could be as high as 1A.
At a minimum, an up-to-date web-browser is required to login and view the web-interface. This can be done on most devices such as smart phones, tablets, laptops, and desktop computers.
No additional software is required to use the system; however a Fleet Management Software is available for monitoring a large number of systems on a single network.
All measured data is stored on an SSD in each individual VIGILANT® Monitor. The SSD is sized to accommodate 20 years of measured battery data. A permanent connection to the monitor is not required for the system to measure and record data.
Update files are available on the Eagle Eye Power Solutions website (see Help Center) and uploaded on the monitor by the end-user. They can be installed over network of via direct connection to the unit. Eagle Eye also offers a service to perform updates if requested.
A newsletter will be released as new updates are available.
The VIGILANT® has a built-in web server with a dedicated IP address (default is 192.168.1.250). The web server can be accessed on a web browser from any PC on the same network via the monitor IP address. The IP address can be set to DHCP or a static. An internet connection is not required, nor are there any cloud based features on the system.
The VIGILANT® system has an Ethernet port for connection to a network or direct connection to a computer. Both access the web-interface and Modbus communication can occur simultaneously over this port.
For hard-wired alarming, the system has (2) dry contact relays.
Port 80 is the primary port for communication and control of the VIGILANT® monitor. If using Modbus port 502 and 0502 are needed.
Currently Modbus TCP is the only external protocol supported. DNP3 protocol is in development for release in 2023.
The following protocols are not supported: SSH, HTTPS, Telnet, and SNMP.
System logs are accessible by Eagle Eye Services only and are used for troubleshooting device failure. Customer accessible system logs may be provided in a future update.
All collected data residing on the VIGILANT® monitor/manager web-server may be accessed via internal networks (if the battery is on-site or available to those networks, – such as remote sites coupled to the company net by wireless or land-line). The system appears as a web site, and can be accessed and navigated as such. If the system is accessed via the internet, again it will be accessible by use of a URL exactly the same as any website.
All data will remain in the VIGILANT® memory for the life of the SSD memory (see the Vigilant Expert data sheet). Download of the data to a company database can be achieved at any time by CSV files, Modbus or DNP3 (2023 release).
When they were introduced over 30 years ago, Battery Monitoring Systems were stand alone systems and seldom integrated into an organizations control and reporting network. With the increase in remote monitoring and the increasing risk of cyber attacks that is no longer practical.
For example, the NERC CIP-003 Standard requires that all electronic access to communicable products that are located within an Electronic Security Perimeter such as a substation. Must have access to these devices controlled by the Responsible Entity which effectively makes a battery monitor an intelligent sensor. Because the VIGILANT® Monitoring System does the basic alarm analysis within the controller it is ideal for this application as it does not require a secondary device to analyze and distribute the collected data, as the previous generations of monitor do.
The VIGILANT® has several means of alarming based on the measured parameters:
Monitor alarm relay: There is a single dry contact relay available for when a critical alarm occurs.
Modbus point: There is a Modbus point available for when either a warning or critical battery alarm occurs.
LEDs: There are LEDs on the front of the monitor that correspond to various alarms on the system.
Web-interface: All alarms are viewable on the VIGILANT® web-interface.
Fleet Management Software (optional): Critical and warning alarms are viewable for all installed systems.
Additional alarming paths are in development, including DNP3.
The VIGILANT® system performs many self-checks on the system sensors and the monitor itself as part of its program. Alarming is available for the following failure modes:
CPU failure/lockup
Loss of power
Loss of communication to sensor bus
Failed or disconnected sensor
The VIGILANT® monitor includes 2 dry contacts standard:
Battery alarm: Occurs when any measured parameter reaches critical alarm level.
Watchdog alarm: Occurs when any of the 4 watchdog parameters occur (see above FAQ)
The maximum power rating of the contacts is 300 watts, not to be exceeded. If the breaking voltage is 300V then the breaking capacity could be as high as 1A.
Hardware, Engineering, & Measurement FAQs
What are the main components of the VIGILANT® system?
The VIGILANT® system includes the following main 4-5 components:
- VIGILANT® Monitor – Stores data, runs web-server, handles communications. (1) monitor per battery system.
- VIGILANT® Sensors – Measures cell/unit parameters. (1) per cell/unit, plus (1) per string.
- Connection Hardware – Physical connection to battery post. (2) clamps or (3) tab washers per cell/unit.
- Wiring Harnesses – Connects VIGILANT® sensor to battery connection hardware. (2) harnesses per cell/unit.
- Electrolyte Level Sensors (optional) – Measures electrolyte level, (1) per cell.
What is the required power supply for the system?
This depends on the model of the VIGILANT® or the chosen method to power the monitor. The system can be powered off the battery or from an external power source. Below are the options to power the system:
From the battery:
- Low voltage: 36 – 72 VDC
- Medium voltage: 95 – 300 VDC
- High voltage: 280 – 580 VDC
External:
- 24 VDC (often used for AC power with a converter)
Do any VIGILANT® components draw power off individual cells?
No, all VIGILANT® components are powered from the monitor, which receives power from the battery charger or an external power source.
What battery parameters does the VIGILANT® Monitor?
The VIGILANT® monitors the following parameters at the specified interval:
- Battery float voltage (15 min.)
- Charger float voltage (15 min.)
- Float current (15 min.)
- Charge & discharge current (1 sec. during discharge)
- Ambient temperature (15 min.)
- Cell/unit voltage (15 min.)
- Cell/unit resistance (Once daily)
- Interconnection resistance (Once daily)
- Terminal resistance (Once daily)
- Negative post temperature (per every cell/unit) (15 min.)
- Electrolyte level (15 min.)
- Ground fault (15 min.)
Does the VIGILANT® check for battery continuity?
Yes, the VIGILANT® monitors the float current in the battery by accurately measuring the potential difference across the cell interconnections; this enables reliable detection if the battery has a continuity fault. In addition, we rely on the ohmic readings from each interconnection.
Does the VIGILANT® measure for resistance, impedance, or conductance? Which parameter is preferred?
The ohmic value of a cell or unit reading can be reported as Resistance, Impedance or Conductance and which value reported is dependent on the perturbation method used. If a DC source is used, the value reported will be a Resistance. If an AC source is used, the value will be reported as Impedance. Both these methods are reporting the change in ohmic value as an increase in the opposition to current flow, whereas Conductance, which is the reciprocal of Resistance, will report the value in siemens or mhos and the value will drop as the battery ages.
In the thirty plus years that ohmic values have been part of a battery maintenance program, while the individual test equipment manufacturers have promoted the value of their specific method and while the values reported will be different, their ability to identify the level of change is virtually the same.
The VIGILANT® uses a DC perturbation pulse, so it reports the value as a resistance.
How is electrolyte level monitoring incorporated into the system?
The VIGILANT® was designed to incorporate the ELM-Series electrolyte level sensors. Each ELM sensor plugs directly into the Vigilant sensor for that cell. This allows the software to display which cells specifically have low electrolyte level alarm. These alarms can be cleared from the software or in the field after a cell is refilled.
How does the VIGILANT® monitor for ground faults?
Typically, battery ground voltage (without fault) should sit midway between battery positive and negative. The VIGILANT® checks the ground potential relative to the battery mid-point and will detect an imbalance if the ground potential is not mid-battery voltage. The closer the ground fault to battery positive (or negative) the signal will have a higher ground leakage current. When measuring for a ground fault the VIGILANT® is looking for a nominal difference of 9% (not adjustable on present system). This to say, on a 120V system with the battery mid-point at 60V, if the ground voltage is below 54.6V or above 65.4V then a ground fault warning will be raised.
Be aware that some systems have one battery terminal intentionally grounded (usually positive on telecommunication systems). If this is the case then the small green wire loop in the monitor should be removed, or, do not ground the monitor chassis. This will prevent the monitor recording a ground fault.
Does the VIGILANT® ground fault monitor interfere with the battery charger’s ground fault monitor?
No, this has been tested with most battery chargers on the market and there has been no conflict.
How does the VIGILANT® test resistance, is it safe for the cell/unit?
Each sensor draws a robust test current for a very short time from each cell, this results in a small momentary change in the terminal voltage. The waveshape and parameters of the change in the terminal voltage are analyzed, and from this the VIGILANT® can determine the cell and strap resistance.
The sensors analyze the cell energy and automatically optimize the test current to maintain a safe level of test. The actual energy drawn from the cell during the test is insignificant to the battery and is not detrimental to the cell in any way.
Why is a higher test current used to measure internal resistance?
Standby batteries are subject to a float current all their service, lives in order to maintain them for instant use. The resulting float voltage is actually an overvoltage of approximately 150 millivolts per cell on top of the cell’s fully-charged natural open-circuit voltage.
Cell internal resistance/impedance is calculated by drawing a current from the cell in a pulse pattern and measuring the change in the terminal voltage. If too low a test current is used, several factors which can adversely affect the measurement come into play
- The change in terminal voltage will be too small to come from the cell itself, but will come from the overvoltage, mainly influenced by the charger. If the float current changes the measurement will be different.
- Battery system noise and ripple can obscure a small test current and lead to adulterated readings
- A low test current means a small response signal; the smaller the signal the less accurate the measurement can be.
Does the VIGILANT® measure the temperature of every cell/unit?
Yes, a temperature sensor is built into every negative post connection from the VIGILANT®. It is recognized in the battery industry that the negative post of the cell is the most sensitive to internal temperature variation, and if ‘acid creep’ is experienced it is inevitably at the negative terminal post first. The negative post is often at a slightly higher temperature than the positive post and in any case terminal posts are a much better indicator of internal temperature than the plastic cell casing, which is a thermal insulator and influenced by the ambient temperature. The VIGILANT® sensor is designed to have an excellent thermal connection to the negative post and is also insulated against the effects of changes in the ambient.
Does the VIGILANT® perform balancing of the cell/unit voltage?
No, the VIGILANT® does not influence or have any effect on the cell/unit voltage. The system is designed strictly for data acquisition and is not intended to change the battery in any way.
Does the VIGILANT® check for battery sulphation?
While not directly measuring sulphation inside the cell, the VIGILANT® measures parameters which can indicate sulphation is present.
In a lead acid battery, when it is discharged, both the positive and negative plates will be converted to Lead Sulphate and return to Lead Dioxide and Sponge Lead when they are recharged. It is important that the battery is recharged as soon as possible, as the lead sulphate will crystallize over time, at which point no amount of recharging will change it back to its original fully charged state.
If the battery is not being charged at a high enough voltage to overcome self-discharge, lead sulfate will form on the plates, initially on the edges but eventually on the surface of the plates, and when it crystalizes, it will block the underlying active material and reduce capacity. Although in the initial stages it will not change the Ohmic measurement, once it affects the surface of the plates it will. Monitoring the individual cell/unit voltages to ensure that they are within the manufacturer’s limits should reduce the potential for Sulphation to occur. A rise in Ohmic value can be indicative of sulphation and prompt inspection of the cell/unit.
The VIGILANT® system includes the following main 4-5 components:
VIGILANT® Monitor – Stores data, runs web-server, handles communications. (1) monitor per battery system.
VIGILANT® Sensors – Measures cell/unit parameters. (1) per cell/unit, plus (1) per string.
Connection Hardware – Physical connection to battery post. (2) clamps or (3) tab washers per cell/unit.
Wiring Harnesses – Connects VIGILANT® sensor to battery connection hardware. (2) harnesses per cell/unit.
Electrolyte Level Sensors (optional) – Measures electrolyte level, (1) per cell.
This depends on the model of the VIGILANT® or the chosen method to power the monitor. The system can be powered off the battery or from an external power source. Below are the options to power the system:
From the battery:
Low voltage: 36 – 72 VDC
Medium voltage: 95 – 300 VDC
High voltage: 280 – 580 VDC
External:
24 VDC (often used for AC power with a converter)
No, all VIGILANT® components are powered from the monitor, which receives power from the battery charger or an external power source.
The VIGILANT® monitors the following parameters at the specified interval:
Battery float voltage (15 min.)
Charger float voltage (15 min.)
Float current (15 min.)
Charge & discharge current (1 sec. during discharge)
Ambient temperature (15 min.)
Cell/unit voltage (15 min.)
Cell/unit resistance (Once daily)
Interconnection resistance (Once daily)
Terminal resistance (Once daily)
Negative post temperature (per every cell/unit) (15 min.)
Electrolyte level (15 min.)
Ground fault (15 min.)
Yes, the VIGILANT® monitors the float current in the battery by accurately measuring the potential difference across the cell interconnections; this enables reliable detection if the battery has a continuity fault. In addition, we rely on the ohmic readings from each interconnection.
The ohmic value of a cell or unit reading can be reported as Resistance, Impedance or Conductance and which value reported is dependent on the perturbation method used. If a DC source is used, the value reported will be a Resistance. If an AC source is used, the value will be reported as Impedance. Both these methods are reporting the change in ohmic value as an increase in the opposition to current flow, whereas Conductance, which is the reciprocal of Resistance, will report the value in siemens or mhos and the value will drop as the battery ages.
In the thirty plus years that ohmic values have been part of a battery maintenance program, while the individual test equipment manufacturers have promoted the value of their specific method and while the values reported will be different, their ability to identify the level of change is virtually the same.
The VIGILANT® uses a DC perturbation pulse, so it reports the value as a resistance.
The VIGILANT® was designed to incorporate the ELM-Series electrolyte level sensors. Each ELM sensor plugs directly into the VIGILANT® sensor for that cell. This allows the software to display which cells specifically have low electrolyte level alarm. These alarms can be cleared from the software or in the field after a cell is refilled.
Typically, battery ground voltage (without fault) should sit midway between battery positive and negative. The VIGILANT® checks the ground potential relative to the battery mid-point and will detect an imbalance if the ground potential is not mid-battery voltage. The closer the ground fault to battery positive (or negative) the signal will have a higher ground leakage current. When measuring for a ground fault the VIGILANT® is looking for a nominal difference of 9% (not adjustable on present system). This to say, on a 120V system with the battery mid-point at 60V, if the ground voltage is below 54.6V or above 65.4V then a ground fault warning will be raised.
Be aware that some systems have one battery terminal intentionally grounded (usually positive on telecommunication systems). If this is the case then the small green wire loop in the monitor should be removed, or, do not ground the monitor chassis. This will prevent the monitor recording a ground fault.
No, this has been tested with most battery chargers on the market and there has been no conflict.
Each sensor draws a robust test current for a very short time from each cell, this results in a small momentary change in the terminal voltage. The waveshape and parameters of the change in the terminal voltage are analyzed, and from this the VIGILANT® can determine the cell and strap resistance.
The sensors analyze the cell energy and automatically optimize the test current to maintain a safe level of test. The actual energy drawn from the cell during the test is insignificant to the battery and is not detrimental to the cell in any way.
Standby batteries are subject to a float current all their service, lives in order to maintain them for instant use. The resulting float voltage is actually an overvoltage of approximately 150 millivolts per cell on top of the cell’s fully-charged natural open-circuit voltage.
Cell internal resistance/impedance is calculated by drawing a current from the cell in a pulse pattern and measuring the change in the terminal voltage. If too low a test current is used, several factors which can adversely affect the measurement come into play
The change in terminal voltage will be too small to come from the cell itself, but will come from the overvoltage, mainly influenced by the charger. If the float current changes the measurement will be different.
Battery system noise and ripple can obscure a small test current and lead to adulterated readings
A low test current means a small response signal; the smaller the signal the less accurate the measurement can be.
Yes, a temperature sensor is built into every negative post connection from the VIGILANT®. It is recognized in the battery industry that the negative post of the cell is the most sensitive to internal temperature variation, and if ‘acid creep’ is experienced it is inevitably at the negative terminal post first. The negative post is often at a slightly higher temperature than the positive post and in any case terminal posts are a much better indicator of internal temperature than the plastic cell casing, which is a thermal insulator and influenced by the ambient temperature. The VIGILANT® sensor is designed to have an excellent thermal connection to the negative post and is also insulated against the effects of changes in the ambient.
No, the VIGILANT® does not influence or have any effect on the cell/unit voltage. The system is designed strictly for data acquisition and is not intended to change the battery in any way.
While not directly measuring sulphation inside the cell, the VIGILANT® measures parameters which can indicate sulphation is present.
In a lead acid battery, when it is discharged, both the positive and negative plates will be converted to Lead Sulphate and return to Lead Dioxide and Sponge Lead when they are recharged. It is important that the battery is recharged as soon as possible, as the lead sulphate will crystallize over time, at which point no amount of recharging will change it back to its original fully charged state.
If the battery is not being charged at a high enough voltage to overcome self-discharge, lead sulfate will form on the plates, initially on the edges but eventually on the surface of the plates, and when it crystalizes, it will block the underlying active material and reduce capacity. Although in the initial stages it will not change the Ohmic measurement, once it affects the surface of the plates it will. Monitoring the individual cell/unit voltages to ensure that they are within the manufacturer’s limits should reduce the potential for Sulphation to occur. A rise in Ohmic value can be indicative of sulphation and prompt inspection of the cell/unit.
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