Here's an example of an old device no longer available. Olimex PIC-P40, what seems to be some version of Panasonic EV Series DC Contactors
(https://na.industrial.panasonic.com/products/relays-contactors/mechanical-power-relays/lineup/automotive/series/2800), Shunt with LED readout and a 900mhz RF modem (not pictured). Particular unit was capable of 180VDC 150AMP.
