Quote:
Originally Posted by SteveJ
I have one just like this with a different brand name to it that has been working apparently well for a year. This is the 350 amp(500 surge) version. They have a 100 amp version for about $25 cheaper. Or you could get the fancy Victron one with the display and Bluetooth to the Victron phone app for $264.
https://www.amazon.ca/Voltmeter-Amme...%2C169&sr=8-10 |
The devil is in the details with battery monitors in general and without seeing the complete instructions it is hard to know the details
There are certain features that are often missing in the some of the lower priced units like the very inexpensive amp hour counters that make them much less useful in real life and the description doesn't say if this unit has them or not.
Almost all show current amps and volts, use a totalizer for amp hours in/out, some show state of charge %, etc. The issue shows up with how they handle the amp hours in/out and the state of charger % as many take it as a straight math calculation of amps over time which will not be accurate over time because of the charge efficiency. It is much less of a problem with lithium as the charge efficiency is nearly 1.0, but is quite large on large on lead acid batteries.
Especially for lead acid, either AGM or wet cells, it is also nice to have a "fully charged" indicator that looks at the amps and volts to battery to determine when both are indicating a full battery. The volts must be at full absorption voltage and amps at the recommended tail amp setting. To be useful these need to be settable items to match your battery bank, size and recommended full charge recommendations. The indicator can be set for a lithium battery though when you figure out what settings to use for your system. The voltage climbs and amps drop very quickly as lithium get near full, so have to catch it where you want to be.
The defaults that Victron puts in the units now are so conservative they are pretty much useless for telling you if the batteries are really full, so the fully charged indicator comes on way early at maybe 85% or so, so they need to be reset to be accurate for fully charged. They appear to do that because most chargers on lead acid don't get the batteries totally full but will indicate they did. I think Victron got tired of telling people their chargers weren't capable of doing the charge accurately so give a matching false indication of full.
The above is why the PD chargers are good, as you can force the charger stages to get the batteries totally full, and indicated as such on the monitor with it set correctly, but it is a manual intervention based on watching the amps/volts to the batteries to see how close it is to the target tail amps/volts. Very few chargers allow you to do that, and doing it automatically in the charger is nearly non existent except for Magnum, maybe Outback, and probably a centralized controlled from the monitor Victron complete system.
Linear Mode
