Ok, first time poster. Dont know much about electronics thats why Im here. I have a boat, we pump water in ballast bags to get a nice wake. I have 3 pumps that fill and empty the bags via one swith. I open or close the valves as needed. Switch up fills , switch down empties. There is a 40amp 12v relay near the pumps. There is a power wire from the battery, power wires from the pumps and two other wires(switch?). The relay is a four prong, automotive realy. Ok, I bought the boat and this is the set up. It worked fined for a couple outings then went out; I bought a new realy and it worked again for only two outings and its out now. What can be causing this relay to go out?? Also I had to replace my battery yesterday. When I jump the relay the pumps work. But just curious, could a bad pump kill the relay?? Is it a short somewhere?
help!
Thanks!
The only thing that can cause the relay to fail is attempting to pull too much current through the relay. Do you have any idea what kind of current the pumps pull.
I will check soon as I get home. Thanks!
Are you using waterproof relays? Most relays are not hermetically sealed, but a few are. If using a relay on a boat I would highly recomend ONLy using sealed relays.
https://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=330-079
You may also want to consider adding 1 relay per pump, instead of 1 relay for all the pumps. This will decrease the current going through the contacts and should increase life.
-------------
Kevin Pierson