¶ LongMon Cell Monitor
Specifications: LongMon-BlockMon-LeafMon Data Sheet PDF
¶ Intelligent Cell Monitoring Unit
- Battery range 2.2V to 5.4V
- Bypass current 0A to 2A (typically 1A)
- Over-temperature protection
- Over-voltage protection up to ±20V
- Noise immune opto-isolated
- Cell temperature and bypass load temperature measurements
- USB monitoring of live individual cell parameters and remote cell diagnostics
- Sealed in black thermally conductive epoxy (robust and safe)
- Red and green LEDs for diagnostics and status
- All parameters are fully remotely programmable and the software is remotely upgradeable.
More details available:
¶ Dimensions
¶ Connection to WatchMonCORE: Requires a 5 Pin IsoMon and Cable
¶ Connection to a WatchMon4 or Earlier: Requires a 4 Pin CMU and Cable
¶ Cell Monitor Pack Design Considerations: Max Ah that a LongMon Can Handle
We recommend 200-300Ah, although please note that this is subjective as others have used them on 800-1000Ah.
Typically we adopt the logic that if a battery is totally out of balance (all full with one empty or vice versa) the system should be able to automatically equalise within ~1 week. Hence, if a LongMon can sustain 5W or ~1.2A bypass and there are 168 hours in a week, this results in approx 200Ah.
The reality is if you go larger, it will take longer.
Remember that this is the worst case and most of the time it's negligible balancing on a daily basis when the pack have been balanced. This requirement is only needed when recovering from a problem or on initial commission if people do not pre-balance. Our customers typically don't pre-balance, hence why we suggested sizing.
1000Ah will take 5 weeks, for this is acceptable but we think it is not ideal.
If you have a large capacity on many cells, consider multiple strings, which have their own pros and cons.
¶ Below is an example of all cells full with 2 still needing to be balanced up to the same SOC%:
¶ How Many LongMons Can be Installed with One WatchMon?
Up to 250 cell monitors.
With the aggregator functionality now we can have one master supervisor listen to up to 70 satellite supervisors, each having 250 cells.
Here is a short video showing the final stages of cell balancing.