IRHAPSODY 12V Continuous Duty Relay, 5-pin SPDT 250 Amp High Power On/Off Starter Relay, Split Charger Contactor for Truck Boat Marine Van Golf Carts

Our power went out, to keep our bed warm, I used a 600 watt pure sine wave inverter all night long to power our king size electric blanket. The voltage on my one122 amp hour deep cycle battery was down from 12.4 to 12.2 by the morning. The next day I charged my deep cycle battery with our car. It has this relay with some extra wires to make a quick charger, using your car as an emergency charger battery charger.We use my deep cycle battery for emergency lighting in four rooms, power my wife's electric recliner and run our 60 inch TV during a power outage. Now our 160 watt electric blanket. A blue flame heater is used for back up heat in a well vented room. 1 20 lb. tank, one day of heat. We have 3 for emergency heat.We have power outages 3 to 4 times a year where I live.If the power remains down, I can charge my deep cycle battery with the alternator from my car. A disconnect switch is needed to remove the engine's battery from the cars electrical system after you start the car. I used this RELAY to disconnect the engine battery and charge my shore power deep cycle battery. When you disconnect the engine battery, the RELAY will switch to the shore power battery, and all of the charging power will go to the shore power battery.It gets the full charge it can take. I charged my battery at 50 amps for 2 minutes, then it dropped to 30 amps. I ran my car at an idle for 20 minutes for a test. It worked fine. I am ready for a cold night. It feels good. Inverter 60 bucks switch $13.00, wire $20.00, battery $90.00 at Walmart ($185.00 + blanket King 95.00 = $280.00).We had the battery, wire and the king size blanket already. Our cost about $95.00

Disclaimer: I am not an automotive electronics professional.However, our RV's stock solenoid that connects the alternator/starter-battery and the house-batteries had failed, and our house batteries would no longer charge while driving. Instead of replacing with another stock solenoid, I switched to this 5-pin SPDT relay, in order to add one new feature without having to lose any existing functionality. We have replaced the house batteries from AGM to Lithium, and the concern with lithium batteries is that since they have such low internal resistance (meaning they charge very fast), they could draw too many amps from your alternator then you really want (i.e. overheating). To remedy this, we plan to add a DC-DC charger to limit the draw from the alternator before the lithium batteries take the amps. However, we still want to keep the "Battery Boost Button" functionality in the RV.This relay/solenoid allows you to do those things.Things that would be helpful for this relay:- you will need 2 insulated female plugs to connect thin wires to 85/86. (would be helpful if included)- the leads for 87A and 87B are quite close to each other, I'm nervous about a short, it would be nice if there was a physical separator between leads to prevent that

I used this on my solar back and it worked perfectly during a power outage. I ran it at 300a.

One of the 2 units I bought, terminal broke internally while tightening. Unit shorted out, unable to use.

Very well constructed for the price you cannot beat it I was skeptical at first but when I opened it up I saw the quality of the craftsmanship and the packaging was good as well