We had just pulled into a campground this afternoon. We had just finished dinner when a loud humming/vibrating noise came from the front bay. It was coming from the area of the hydraulic tank. The noise lasted about 30 minutes and then stopped. If it matters it's 32 degrees out. Any idea as to what this might be?
Humming sound in Front
- Thread starter WCW
- Start date
We did (actually still do) have a noise that comes from the front of the RV but not when we are disconnected from the truck. It only happens when we are connected to the truck and then put the truck into gear. I called Mor Ryde and Rob told me that the noise is ok. But, I don't think this is the same problem as you are having. Good luck with your problem.
Called my service tech back home and he called Dexter. They told him that the temp drop was causing the noise and after the fluid in the actuator heated up the noise should stop. We drove 250 miles today and the noise is still going. I'll call Dexter tomorrow. I wish I new how to stop the noise overnight. It's really loud.
Mrburnsie2u
Member
The humming sound is coming from resonance from the metal lid on the transfer switch box. The coils vibrate at 60htz and transfer that small vibration to the lid of that box. Take the lid off and I bet your hum will go away. Now solving the problem has still eluded me.
mlpeloquin
Well-known member
Try a thin sponge gasket material for doors. You can find it at the hardware store. Self adhesive on one side over the lip of the transfer switch box. Then install the cover. It should dampen the cover and stop it from vibrating. Cannot stop the transfer switch relay from making the noise, but you might be able to put some rubber shock mounts under it's mounting screws to help as well.
wdk450
Well-known member
I'm thinking that if the transfer switch box cover is CAUSING the noise by being magnetically attracted by the relay coil, you could fabricate a new box cover out of sheet aluminum, which is not affected by magnetism. If the cover is simply harmonically oscillating due to vibrations from the rest of the transfer relay, then vibration dampening materials would be in order. Maybe gluing thin plywood to the cover faces to make them more stiff?
SNOKING
Well-known member
Saw this while searching why relays are pulled when on shore power. Chris
Fantastic DC relay type transfer switch. Completely silent. Swapped out a noisy Progressive PD52 AC Contactor for this switch and the silence is deafening.
https://www.amazon.com/Elkhart-LPT50BRD-Automatic-Transfer-Switch/dp/B007HS0ONG/ref=pd_sbs_263_3?ie=UTF8&psc=1&refRID=4CZ0GCMTXH5ZVFPD48SG
Jesstruckn/Jesstalkn
Well-known member
wdk450
Well-known member
The disk brakes actuator should NOT be running except when it receives a braking signal from the truck. If the actuator keeps running continuously, the brakes would be constantly engaged, and the rig would not move. It should be directly wired to the battery system, without a fuse or circuit breaker, for safety sake. If you think that this is the noise source, temporarily remove the actuator's red wire from the battery system, and see if the noise stops. If it is continuously running when parked, there is something wrong with the braking system.
danemayer
Well-known member
When a trailer has two power sources, one being shore power and the other being an on-board generator, there needs to be a way to 1) ensure that only one device applies power to the coach at a time, and 2) ensure that the generator can't put power back on the shore power supply lines where it could injure someone working on the electrical system.
A transfer switch has two inputs; one from shore power and the other from the generator. There is one output - to the circuit breaker panel. One input is active at any given time.
Some trailers have the Generator Prep option, but not the generator. The transfer switch is part of the Generator Prep option.
