Best New ATS (Automatic Transfer Switch)

[fagnaml]

A few days ago I shared my experience about my Iota Engineering ATS overheating and catching fire.  Now I need a new ATS and need advice from the forum on the best ATS available.   RV Masters in Houston gave me these three switches to consider:

• Parallax Power Supply ATS 503 --> http://www.parallaxpower.com/transfer-switch-50a-120-240v-ats503 --> $450
• WFCO T57 -->  http://wfcoelectronics.com/product/wf-t-57/#tab-5b071284d5eeb --> $230
• Progressive Dynamics PD52DCS --> https://www.progressivedyn.com/rv/automatic-transfer-switches/pd52dcs-pd52s-240-vac-50-amp-automatic-surge-protected-transfer-switch-the-silent-ats/ --> $390

The WFCO T-57 from a "cords in/out" configuration best resembles my Iota ATS with the shore line entering the bottom of the box with generator "in" and power distribution "out" cords on the sides of the box.  While the WFCO ATS is the lowest cost, price is not the driver for me.  I want the "best", most reliable ATS available to help assure I never experience an overheated ATS again!

Reviews on Amazon for all three switches are generally quite good (each switch has one negative review) so if cost and especially ease of installation were the top concerns, I'd pick the WFCO switch.  What advice does the Forum have for these three ATS's?   Are there other brands of ATS's I should consider?

Thanks for the help!

[five]

After reading your earlier thread, I looked up the make/model of my ATS.  It is a Surge Guard Model 40250.  I binged it and it came up on the Camping World site, reg price $880, sale price $663....have no idea why this model is so expensive, although it has worked flawlessly.

https://www.campingworld.com/surge-guard-automatic-transfer-switch-with-rv-power-protection

[desertdeals69]

One of the main reasons a transfer switch overheats and catches on fire is loose wire connections.  This can happen to all switches.  Wires should be checked and tightened at least once a year.

[manholt]

DD69.

Totally agree and I hope Mike understand that now! 

Mike, mine is the same as FIVE has!  When I had the 2011 Tiffin, Allegro Bus...it was the same as now.  Have only had one Progressive on a 2007 WB Tour and it kept sticking in Shore power mood, had to hit it to get it to accept Generator (exchanged 3 times by WB in 5 years)!  The last time was in 2009 and it was a Surge Guard...worked great until I traded for the Tiffin in January 2011.

Hope it's been some help! 

[nosticks]

This is what remains of my ATS.  Not the manufacturers fault.  It was the build process that made connections inside the ATS with wire nuts attached to short pre-stripped pig tails.  Wire nuts is nuts on a shaking vibrating earth quake on wheels.  This was my middle of the night end to my 600 mile Christmas vacation after two days into a ten day trip.  It was especially alarming as the ATS is located under the bed.  Smoke alarms worked fine but choking on burned plastic and wires will wake you faster.

My point is check those connections.  My coach was new and on it's first long distance trip.

[fagnaml]

To no surprise, my XtraRide extended warranty plan will only pay for a "like kind" replacement of my overheated Iota Engineering Brand ATS.   Of the ATS's suggested by the RV Masters repair shop, XtraRide said the WFCO T57 ATS is the most similar to the Iota in terms of functionality.   The other switches are an "upgrade" which XtraRide will not fund (especially switched with built-in surge protectors).

So, I'll have the WFCO T57 switch installed.   Over time I'll let the forum know how this switch performs.  For surge protection I'll continue to use my 'portable' Surge Guard Protector --> https://www.campingworld.com/portable-surge-guard-protectors-50-amp

Now a follow-up question -- What type of "torque screw driver" does the forum prefer?  I need to purchase one for my tool box to use for what will now be an annual ATS busbar screw tightening party!

[hermanmullins]

I  would suggest a full set. A 15 to 55 and maybe larger. If you haven't bought any dry wall screws, they are now Torx Drive. They include a driver bit in each box.

I know the drive system well. I sold they in 1969 through 1972. Great system. I introduced the screw to Lufkin Trailers for their floor boards.

Herman

[jleamont]

22 minutes ago, hermanmullins said:

Lufkin Trailers

WOW, there's a name I haven't heard in a LONG time .

Right up there with Brown and Dorsey.

[fagnaml]

A quick update on my ATS saga and a new question for the forum.   XtraRide approved the replacement of my fried Iota ATS with the WFCCO T57 as the best "like kind" ATS.   RV Masters will do the work which should be done in a couple of weeks (RV Masters currently has a 13 day back-log of work).

My new question for the forum comes from my father-in-law who is a long time retiree of Public Service Company of Colorado (now Xcel Energy) and a big-time DIY home re-modeling guy including home electrical systems.  He asked if automatic transfer switches have "problems", why not use a manual transfer switch that is very commonly used for connecting a generator to a home distribution/breakers box?  He stated a manual transfer switch would offer more reliability by not having a solenoid, circuit board, etc. that could fail. 

My response was "I don't know why a manual transfer switch is not used by I know a great group of motorhome owners that would have the answer !".  

When I think about the 2011 Tracer Executive 30 foot travel trailer I previously owned, it had a manual transfer switch -- ME !!   I either plugged the TT's 30 amp cord into shore power at an RV park OR plugged it into my parallel Honda 2000 generators when boon-docking at an LSU football game.

So, Forum, why wouldn't a manual transfer switch work if such a switch is made for RVs, work?  

And now the follow-up question which completely eliminates the need for a transfer switch.  The 50-amp power cord conceivably can be wired directly to a motorhome's distribution panel (same as in the TT that I owned).   The "cord" from the on-board Onan generator could terminate in a 50-amp outlet in the compartment where the power cord is stored.  Then depending on where the motorhome is parked, the 50-amp power cord could be plugged into shore power or plugged into the generator.  Why wouldn't this arrangement work (which is the same as any travel trailer has) ??

[wolfe10]

Mike,

Indeed, there are several good/safe ways to use multiple 120 VAC sources.

Most RV's use ATS's because they are "automatic"/require zero owner work.

Most marine applications DO use manual switches and they are a viable option in an RV.  More KISS theory, but do require owner "work".

And certainly another option is to manually plug shore power cord into outlet supplied by generator.

As with all 120/240 VAC wiring, you do need to know what you are doing!

[kaypsmith]

1 hour ago, fagnaml said:

And now the follow-up question which completely eliminates the need for a transfer switch.  The 50-amp power cord conceivably can be wired directly to a motorhome's distribution panel (same as in the TT that I owned).   The "cord" from the on-board Onan generator could terminate in a 50-amp outlet in the compartment where the power cord is stored.  Then depending on where the motorhome is parked, the 50-amp power cord could be plugged into shore power or plugged into the generator.  Why wouldn't this arrangement work (which is the same as any travel trailer has) ??

During the building stage of my coach, I used this same configuration and is still in place with the addition of an IOTA brand ATS. I did this as a backup system in the event of the ATS failure. While installing the ATS, I tinned all wires, dipped them in NO-LOX and tightened them. Now I do a six month retightening scedule on both the ATS, my inverters, converter, and the  breaker panel, I am in the eigth year with no need to use my work around, "knock on wood". The manual system will work great, but I enjoy the comfort of not having to deal with another chore. And of course I do turn off the AC units when the ATS is in the process of changing over.

[obedb]

Brett's last choice would be my do-over if I lost another transfer switch. Our first class A was gas powered. The coach 50amp power cord either plugged in to generator output or park power 50 Amp. It worked very well. Never lost a transfer switch because it did not have one😉. Carried adapters for 30AMP power or the occasional 15AMP power. Yes they did exist 30years ago. 

Yes Carl and others. It was wired for 50AMP power. 34 feet, with two a/c s, two furnaces, insulated tanks heated by the rear furnace, a sit down tub for the better half with sliding doors and a shower in there for me.

It was a winter time coach. Dorchester Campground well above Gunnison at 9700 or so feet and overnight temps in the high teens in late September. The sky was beautiful at night.

Oh by the way! The ATS on our newly acquired  2003 Phaeton 40ft diesel failed in 2014  before we got it headed west on our first trip. Just another chore  in order to feel ready. Next time I would convert to basic tech.

[desertdeals69]

9 hours ago, fagnaml said:

A quick update on my ATS saga and a new question for the forum.   XtraRide approved the replacement of my fried Iota ATS with the WFCCO T57 as the best "like kind" ATS.   RV Masters will do the work which should be done in a couple of weeks (RV Masters currently has a 13 day back-log of work).

My new question for the forum comes from my father-in-law who is a long time retiree of Public Service Company of Colorado (now Xcel Energy) and a big-time DIY home re-modeling guy including home electrical systems.  He asked if automatic transfer switches have "problems", why not use a manual transfer switch that is very commonly used for connecting a generator to a home distribution/breakers box?  He stated a manual transfer switch would offer more reliability by not having a solenoid, circuit board, etc. that could fail. 

My response was "I don't know why a manual transfer switch is not used by I know a great group of motorhome owners that would have the answer !".  

When I think about the 2011 Tracer Executive 30 foot travel trailer I previously owned, it had a manual transfer switch -- ME !!   I either plugged the TT's 30 amp cord into shore power at an RV park OR plugged it into my parallel Honda 2000 generators when boon-docking at an LSU football game.

So, Forum, why wouldn't a manual transfer switch work if such a switch is made for RVs, work?  

And now the follow-up question which completely eliminates the need for a transfer switch.  The 50-amp power cord conceivably can be wired directly to a motorhome's distribution panel (same as in the TT that I owned).   The "cord" from the on-board Onan generator could terminate in a 50-amp outlet in the compartment where the power cord is stored.  Then depending on where the motorhome is parked, the 50-amp power cord could be plugged into shore power or plugged into the generator.  Why wouldn't this arrangement work (which is the same as any travel trailer has) ??

Its not the switching method used that is the problem.  The wire connections are where the heat is generated when they become loose or have too much resistance.  This can happen on the cable end plug as well.

[richard5933]

Every time I read about someone's ATS failing (which seems to happen with some regularity on this and other forums) I am thankful that we have a purely manual switch. Almost makes up for the inconvenience of having a manual switch, but not quite. Ours came with the Kohler generator and is labeled as such, and it's located in a control panel just above the outside 50-amp receptacle where the shore power cordset plugs in. This is the same control panel where the generator start controls are (also manual).

Our previous coach also had a manual transfer switch, which I replaced with a new one from Blue Sea. They make a great manual switch that works great with 50 amp service. We used one that switched both hot lines (L1 & L2 as well as the neutral).

Of course, the whole reason for using an ATS over a manual switch is convenience and not having to pay attention to where the power is coming from. The system just switches to the highest priority power source if it's available. If not, it goes to the next highest priority.

As to the question about why not permanently wire the shore power cord to the distribution panel without a transfer switch? That one is easy, as you never want to have the possibility of having both the shore power and the generator connected at the same time. Let's say you are plugged into shore power. For whatever reason power goes out so someone starts the generator. Now you're back feeding the pole with deadly current and who ever is downstream has no idea that you're running a generator. Same reason that home generators require a transfer switch.

I've read about people that set up their rigs to either plug in the shore power cord OR a power cord running from the generator. They manually go down to the bay and unplug one cord and plug in another when they want to switch power sources. Problem there is switching in the middle of the night, when it's raining outside, or at other equally inconvenient time. Inevitably the wrong cord will be plugged in when you pull over and decide to run the generator for some reason at a rest stop, etc.

I'd love to see a chart with a listing of parts that fail, listed in the frequency of failure. My money would be on ATS being at the top of the list, with remote battery switches running a close second. Anyone know if this forum supports surveys? If so, perhaps I'll put one together and we can see just what has failed people the most.

[wolfe10]

10 hours ago, desertdeals69 said:

Its not the switching method used that is the problem.  The wire connections are where the heat is generated when they become loose or have too much resistance.  This can happen on the cable end plug as well.

 

Agree, loose connections are the #1 killer of ATS's.

#2 would be burned points from switching under heavy loads.

 

[fagnaml]

A final update for the forum. 

A couple of weeks ago RV Masters in Houston installed a new Progressive Dynamics PD52DCS ATS (which includes a surge protector) to replace the "fried" Iota Engineering brand ATS.   Surprisingly to me, XtraRide (my extended service warranty provider) preferred the Progressive Dynamics ATS because of its metal housing and metal buss-bar construction.   My cost was just the $200 deductible for my XtraRide warranty.

RV Masters, who does good work for me, found the cause of the electrical short that cause the Iota ATS to fail was a loose ground wire connection behind the buss-bar.  This connection is "original construction" of the ATS and was not accessible to re-tighten the screw.  The power cord connections/screws on the front of the buss-bar (shore line, generator line, and the line to the power distribution panel) were all tight (except for those that were burned!).  

Annual check of all wire connections in my new ATS now goes on my "to do" list a year from now.   This weekend I'll check connections in my power distribution panel.

My one "complaint" with RV Masters this time was the timeliness of getting the work done as during the peak of RV season they have a two to three week backlog of work to do with 85-100 RVs (mostly motorhomes and fifth wheels) inside their fence every week!

[five]

56 minutes ago, fagnaml said:

 

....Annual check of all wire connections in my new ATS now goes on my "to do" list a year from now.   This weekend I'll check connections in my power distribution panel....

Good idea, I check all wire connections, that I can see and reach, annually.

[wolfe10]

26 minutes ago, FIVE said:

Good idea, I check all wire connections, that I can see and reach, annually.

An EXCELLENT IDEA!

[jleamont]

I am currently shopping for a replacement ATS WITHOUT EMS. We have the the original IOTA that was installed in July 2001. No issues with it but its time for an upgrade. I did get information from one of the forums electrical experts, looking for any real world experience.

Anyone have a preferences, past experiences etc? Our coach is a 50 amp with a 7500 Watt Generator. This so far is the runner up due to its reviews on the web seem very positive; 

https://www.pplmotorhomes.com/parts/electrical-plumbing-lp-gas/rv-electrical-systems-and-accessories/transfer-switches/transfer-switches-110-volt-automatic_ES50M-65N?gclid=EAIaIQobChMI1qHA99iI3wIVUUwNCh1zqAOnEAYYASABEgJ9d_D_BwE

I prefer to use the portable EMS on the tower vs one built in. Our coach had a progressive system hardwired that I removed when I realized it wasn't working as it should.

[wildebill308]

Looks good to me. 

Bill

[jleamont]

Think I am going with this one. Mostly for its quality and availability. Anyone currently running this ATS or have any experience with it or the Manufacture?

https://www.progressivedyn.com/rv/automatic-transfer-switches/pd52-240-vac-50-amp-automatic-transfer-switch/

 

[rwsplace]

Interesting forum.  My ATS is not detecting 50 amp from shore power.  Would like to inspect the connections inside.  How do I remove the ATS face panel without tearing it off?

 

Thanks

[wolfe10]

The ATS (Automatic Transfer Switch is usually a metal or plastic rectangular box with lid held on by screws.  There will be 3 large cables into it:  Shore power IN, Generator IN and OUT to coach main 120 VAC breaker box.

Not aware of any OE ATS's that "detect" anything--- they either pass through power from shore or generator.

Please tell us exactly what device you are referring to.

 

And, have you verified that the outlet is, indeed a proper 50 amp outlet:

Outer straight to outer straight= 240 VAC

Either outer straight to center round or center straight= 120 VAC

Center round to center straight= 0 VAC

[rwsplace]

I have a 50 amp EMS Load Meter.  On the left side of the panel it shows service type.  I connect my 50 amp power cord to shore power and turn  on breaker.  The meter panel shows 30 amps.  It started this a couple of months ago.  Prior to that it always showed 50 amps.

Connection problems??

Edited May 31, 2019 by rwsplace
misspell

[wolfe10]

Have you confirmed the readings at the CG pedestal  I posted above (ONLY IF YOU ARE SAFE WORKING AROUND 240 VAC)?

That is the first step in diagnosis.