Purchased this thing via Amazon.
Received device yesterday, no user manual. Searched on line for “VAC8010F-80V” and found what looks to be a .pdf manual for this product. Got thing hooked up per the schematic in that manual. Battery is 12 Vdc, 2x20Ah SLA cells, on a solar PWM charger. Batteries are fully charged (14.4 Vdc) and in good shape. Disconnected batteries from charger.
Through a 12 V – 5 V dc-dc switching converter, connected 4 RTL-SDR-equipped Raspberry Pis and a DLink gigE Ethernet switch (total of about 1.5 A load at 12 Vdc). Device displays -1.6 A current draw, a little high from what my Fluke meter says at -1.5 A. Not bad!
The wireless function is kind of awesome – it just works. The range is at least good enough for having the sensors at the battery and the display head several meters separated, with some house walls in-between. The device uses the NRF24L01 chip from Nordic, so the transmission is in the 2.4 GHz band. I have multiple 2.4 GHz Wi-Fi units in the house, I can’t see how the link degrades, but it seems to be fine. It appears that one sensor unit can communicate to many display heads, or many sensor units can communicate to a single display head. Haven’t experimented with that.
The display is bright and very readable. The three buttons, from top to bottom, are “up”, “select/change”, and “down”. The function of some of the settings is a little hard to determine from the found manual, but I’ll survive. The temperature sensor is a ~100 cm long cable with temp sensor in a ring lug. I have it in-between the two batteries, and shows 28 C, which is close enough.
So the hardware is nice, but the software sucks. Seriously not good. I have had this running now for about 40 hours; the voltmeter function works fine, the current meter appears to accurately show positive current, and the temp sensor works fine, that’s about it. The running Ah and Wh meters just don’t do anything useful. I have 40Ah of 12 V SLA battery, I programmed in via the BAT function the 40.0 Ah size, I discharged the batteries a while until it reached 38.467 Ah. Then I applied a charge to the battery through the circuit, the battery capacity stayed at 38.467 Ah. The battery voltage has continued to increase to full charge, so that’s working. The BPC value is static at 96%. I tried to reprogram the BPC to 100%, but it won’t accept the value. I’ve tried changing the battery capacity to some other value to get it to reset the counters. It will not show negative current (power flowing into the battery from the solar charger). Not sure what to do about this. Probably will return it unless I get some answers soon. I guess I’ll have to wait until Sunday night (Monday in China).