Thor Forums

[javelin]

The latching relay is meant to be powered momentarily to either operate or release its main contacts. They then remain in that operated or released state until the control coil is again powered in the correct polarity to either operate or release the main contacts again. That is why your coach and chassis disconnect switches at the door are momentary operation with return to center off position. Many latching relays can be damaged by keeping them energized. The interconnect (emergency start) relay is meant to be continuous duty because in some coaches the battery control system energizes this relay to allow charging of both coach and chassis batteries together for longer term charging. Emergency starting push buttons are momentary also and only close the interconnect relay when they are being pushed. So, I would suggest that you keep the original electrical design intent of the manufacturer with what you have. If you change a latching relay to continuous duty then your stair switches would also have to change and you would be drawing current through the coils continuously when relays are operated. Unfortunately owning an RV is not cheap and repairing them can hit the wallet too, but redesigning your electrical system also comes with some potentially dangerous consequences (like fire) unless you are an electrical design expert. Your chassis battery latch relay may not be the problem....it could be a 5 amp fuse on the relay or the stair switch as discussed previously.