DC 9 in 1 Battery Monitor Meter with Shunt, 0-200V 0-100A LCD Display Digital Current Voltage Power Energy Meter, Easy Installation Multimeter Voltmeter Ammeter for Cars RV Solar System

Works as it should. Came quickly. Only thing the directions are a little difficult, but for the price not a problem.

I purchased the 100amp version and was pleasantly surprised by the accuracy - even when running a 0.5amp load.. Accuracy was confirmed for current and voltage readings with calibrated multimeters.Easy setup, the diagrams in the instructions are very clear and are conveniently reproduced on the back of the meter itself. The meter frame has snap fit tabs for mounting in a panel, cabinet or case.The interface for setting the meter to the correct voltage range for your batteries (which you must do to get accurate state of charge info), clearing readings, etc is a little fiddly and inconvenient, but works just fine.Keep in mind this is a meter only, it will only take measurements of how much power passes through it, it isn't smart enough to track charge/discharge, and will not do anything to prevent over charge or overdischarge of your batteries.

Would be 5 stars, but two things: it is 5/16 which is annoying because most things around the 100A level are 1/4, and only 2 of the included wires have ring terminals and are comically, I mean laughably, short. Like come on guys, what 100A power system has positive and negative terminals within 6 inches of each other that don't need ring terminals? Change the red/black battery terminal wires to 36 inch and at least throw the ring terminals in the box.

I am using it for a dingy with 55 lb trolling motor and a 50 Ah LiFePo4 battery, and it is perfect for this role.1. all info you need on one screen - voltage, current, Ah/Wh, remailing capacity. Having battery internal resistance and load resistance computed is also very useful.2. it memorizes accumulated values (Ah/Wh) when powered off - no need to use an optional backup source. You manually reset these values after fully charging your battery.3. it also measures all parameters when charging (charger connected to "load" terminals) - so you have exact Ah/Wh pumped into the battery even when your charger doesn't show it.Overall, a well designed device. Instructions in English good enough, readable and clear.

The manual is written in horrible Chinglish, no surprise there. If you could program a VCR or alarm clock, you shouldn't have any difficulties with this one even without any instructions. It's basically one button with 2 choices - short and long press.But the voltage this gadget displays is consistently 0.2v higher than both my built-in voltmeter and the standalone multimeter show. So while it's easy to make an adjustment (in my head), I'm not sure I can actually trust it with the current (A) measurement. So one star off for the useless manual and one for the inaccurate reading.

This was easy to install and provides much better information than the simple 4 dot battery level on our camper.

salió muy bueno.

This review is for the 100A model tested with 3.2V, 320 Ah LiFePo4 bank and 12v 60Ah car battery measuring charge current.12V Battery:Current reading is consistently 2-3% low from 0 to 10A when cross checked against both my Fluke 289 and 189 multimeters and 4% low at 20A using another shunt known to be .05% accurate. Did not test anything higher but I would assume further decreased accuracy at even higher currents. This is below the advertised accuracy of 1%.There seems to be some bizarre ground loop anomaly that causes a false 40 to 60 mA reading when the positive battery terminal is disconnected from the shunt and any sort of external power supply/charger is connected to the negative lead, even when it’s a floating power supply.3.2V Battery:You have to hook up an external power supply when the voltage is below 8v so this is absolutely useless for use with a standalone single or double cell LiFePo4 pack or 6V SLA battery. However I tried using it with a 3.2V battery bank and additional external 12v power supply per the instructions and got some really strange behavior. The charge rate was measured somewhat accurately, but low until about 6A, then from 6A up the readings were all over the place with error as high as 100%. The device completely malfunctioned.Not For Ebike with regenerative braking:Another limitation that others have mentioned is that this reads both positive and negative current flow as positive. This means that this device will not work properly with an E-bike that has regenerative braking.User Interface/Functions:As for the actual functions, display and user interface. I like that its easy to scroll through the settings with a single button, but I don’t like that you have to reset the Ah, Wh and run time separately. It takes a total of 6 long button presses and 9 short button presses (L,S,S,L,L,S,S,S,L,L,S,S,S,S,L). Please redesign this thing to make reset all the first menu option.Amazon would not let me upload photos. Bummer.