About 6 months ago I had Camping World install a Progressive Industries EMS 50amp system to our Montana Big Sky. During the last 2 weekend trips we have noticed a loud "hum" from the EMS unit. At first I thought it was the converter.....replaced it twice (Progressive Dynamics warranty)but alas problem not resolved as I was replacing wrong unit. What would cause the "hum"? I have placed my hand on the unit and there is a slight vibration....which I am sure is causing the hum.Any ideas? I have not contacted Progressive Industries yet...will do that next week. Thought I'd ask the experts for your opinions!!

Mine does the same occasionally. Cannot hear it in the rig, but if I am standing outside by the compartment where it is installed i I can hear it in a quiet environment. Never worried about it.

Just the relay coil. PI has lifetime warranty if the noise is that annoying.

I called PI on mine, they had me take apart the relay and blow out and dirt. When that didn't work they sent me another relay.Edit... Changed to PI

Progressive Dynamics are known to emit a hum. Especially if installed inside the RV. If you're on a "post" unit, you'll also hear the hum, but you need to be close to the unit to hear it. In other words, no worries!By the way, Progressive Industries has a lifetime guarantee and great customer service, whereas "that other company" has a 1 year and lousy customer service!

I just installed the 30 amp with remote display. I did notice a slight hum move a foot away you don't hear it. After retiring I worked for a company that built and repaired car washes they use a lot of AC powered relay a hum from them was common. My only concern is when you install one make sure the wires are fully in the terminal and tightened securely.

Humming from Progressive Industires EMS 50 amp system

11 Replies

falconman
Explorer
Mar 29, 2015
After you go through all the suggested regiments about cleaning the contacts to reduce the hum they will likely send you new contactor assembly. This will require you to disassemble and reinstall the new one. I hope it's in a convenient spot. When I reinstalled mine in our new rig I put plugs on each end to make it easier to remove and handle any future repairs if necessary.
SoundGuy
Explorer
Mar 28, 2015
RVing 4 FUN wrote:
During the last 2 weekend trips we have noticed a loud "hum" from the EMS unit.

At first I thought it was the converter.....replaced it twice (Progressive Dynamics warranty)but alas problem not resolved as I was replacing wrong unit.
What would cause the "hum"?

The answer is obvious ... your EMS unit hums because it doesn't know the words. :S

You're welcome! :B :B
sdetweil
Explorer
Mar 28, 2015
thanks for this topic. I installed the same 50amp EMS unit this week and an esco ES50M-65N transfer switch, in the same under kitchen cabinet bay as the converter.

I just did the compressed air on the EMS unit and the noise is reduced.

I need to do the same on the ATS as well.
RVing_4_FUN
Explorer
Mar 28, 2015
Thanks for the replies. Good to know it isn't going to blow up the 5th wheel.
The hum is something that bothers my wife a lot more than me but it can be loud at times.
I will call PI sometime early next week as the unit is only about 6 months old and see what they suggest.
I like and will try the mouse pad idea this weekend to see what impact that has.
Great to have all you for resource folks. Get out and enjoy those units. Weather here in Oregon is darn near perfect!!
Thanks again for your help.
D_E_Bishop
Explorer
Mar 28, 2015
I am not saying that what we did at work to reduce armature hum in relays is feasible in RV converters, I'm just relating what we had to do.

All of our 120vac relays had a thin piece of steel welded to the armature where it touched the coil core. We had thousands of relays in use on the street and we had complaints from folks living nearby. It seams that some folks are highly susceptible to the 60Hz sound.
tvman44
Explorer
Mar 28, 2015
The relay, probably needs to be changed. Call PI, they have a lifetime warranty that is excellent. As said the other company sucks.
cmarq
Explorer
Mar 28, 2015
I just installed the 30 amp with remote display. I did notice a slight hum move a foot away you don't hear it. After retiring I worked for a company that built and repaired car washes they use a lot of AC powered relay a hum from them was common. My only concern is when you install one make sure the wires are fully in the terminal and tightened securely.
FrankShore
Explorer
Mar 28, 2015
Progressive Dynamics are known to emit a hum. Especially if installed inside the RV. If you're on a "post" unit, you'll also hear the hum, but you need to be close to the unit to hear it. In other words, no worries!

By the way, Progressive Industries has a lifetime guarantee and great customer service, whereas "that other company" has a 1 year and lousy customer service!
Padlin
Explorer
Mar 27, 2015
I called PI on mine, they had me take apart the relay and blow out and dirt. When that didn't work they sent me another relay.

Edit... Changed to PI
time2roll
Nomad
Mar 27, 2015
Just the relay coil. PI has lifetime warranty if the noise is that annoying.