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MagneTek ATS 100 Type 1 Time Delay hack. OEM 2001.

October 12, 2022, 09:54:50 pm

I'd like to eliminate the time delay on the Inverter leg and the shore power leg....2 different boxes.  Everything in my coach ATS (both of them) have a time delay.  Tried switching inputs on both boxes to no avail...returned to the way I found 'em.

Anyone have procedure/pictures of which wires to do what to, in order to eliminate the time delay on the Magnetek ATS 100's?  Nothing in my manuals, I've looked everywhere on the interwebs, and can find nothing detailed.    TIA,  Woody.

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Re: MagneTek ATS 100 Type 1 Time Delay hack. OEM 2001.

Reply #1 – October 13, 2022, 10:21:00 am

Woody,

What is the problem with the time delay?  I'm just asking because I am curious.  It sounds like you want the power source transfer to be instantaneous.  Is that correct?

I was advised to turn OFF all big loads before switching AC power source between shore and generator, then turn them back ON.  Supposedly helps protect the contactors in the ATS box and extend their service life.  Same procedure going the other way (gen to shore).  If one follows this procedure, the time delay in the ATS probably wouldn't matter.

Like I said - not criticizing - just curious.

I don't see anything in the manufacturer data sheet that explains what component actually creates the time delay.  Some sort of thermal delay coil built into the contactors?  Just guessing...

http://www.rialtainfo.com/model_info/modifications/modification_images/automatic_transfer_switch_Parallax_ATS30_Owners_Manual.pdf

Transfer Switch - All Things Foretravel

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Re: MagneTek ATS 100 Type 1 Time Delay hack. OEM 2001.

Reply #2 – October 13, 2022, 10:26:17 am

If you are tired of satellite or something rebooting, buy an U.P.S. (uninterrupted power supply) and put it in the circuit you don't want to flash. Cheap work around for me until I get the small inverter installed.

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Re: MagneTek ATS 100 Type 1 Time Delay hack. OEM 2001.

Reply #3 – October 13, 2022, 11:21:07 am

Woody,

Reading your question a second time, it sounds like your big concern is the transfer between shore power and inverter power.  In that case, I agree that a time delay is neither necessary nor desirable.

Our '93 model U280 came with a manual transfer switch for the inverter.  When we replaced the old stand-alone inverter with a modern Magnum MS2812 inverter/charger, we eliminated the OEM manual transfer box.  The Magnum inverter has a internal transfer switch that automatically selects between shore power and inverter power.  If we are plugged into shore power (and we have the inverter function on the Magnum turned ON) then if shore power fails the inverter takes up the AC loads (on the inverter sub-panel).  This transfer is so fast that no electronic devices in our coach "see" the change in power source.  Same when going the other direction - if shore power is restored the inverter drops out (battery charger comes ON) and shore power takes the loads with zero delay.

Have you checked to see if your inverter has AC pass-through with an automatic transfer switch?  I assume all modern inverter/charges have this function built in.  You may be able to eliminate at least one of the ATS boxes with some circuit wiring modifications.

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Re: MagneTek ATS 100 Type 1 Time Delay hack. OEM 2001.

Reply #4 – October 13, 2022, 01:18:53 pm

Curious as well, as when we lose shore power, our inverter is instantaneous, so no clock resets necessary or TV interruption.
On our initial plug in to shore, we have a time delay to check system for any issues, like open neutral, ground, etc.  That is because of our Progressive EMS system I hard wired before both transfers to eliminate any issues with either shore or generator.
Always willing to learn something new.

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Re: MagneTek ATS 100 Type 1 Time Delay hack. OEM 2001.

Reply #5 – October 13, 2022, 08:30:33 pm

Woody,

ATS-100 transfer switch is used for gen/shore and on some Foretravel models a 2^nd ATS-100 is used for gen-shore/inverter. ATS-100 has a built in delay designed for a generator delay, but no delay is needed for the 2^nd ATS.

Looking in on the floor of the ATS-100 you will see a small, not tall, square time delay relay with 5 terminals. Follow back from inverter contactor (relay) coil to time delay and you will be able to figure out which wire is hot with inverter and which wire controls contactor coil. Jumper or bypass the small time delay relay for instant inverter closure. Use a meter to identify time delay relay connections.

Follow my hand drawn diagram if it helps.  You will see a the hot 120v inverter wire that can go directly to coil.

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Re: MagneTek ATS 100 Type 1 Time Delay hack. OEM 2001.

Reply #6 – October 13, 2022, 10:30:04 pm

Thanks for the schematics and pic Barry.  I'll still need to know more specifics, as I'm fundamentally electron illiterate...."should I cut the red wire or the blue wire": stolen from the proxy bomb disarming scene in literally any cliff hanger movie.

To answer the comments/questions, I have 2 MagneTec ATS boxes.  They've been worked on (by whom?) since factory since some of the wires have Sharpie writing on them...not too legible.  The top box is wired to shore power and generator...I tried swapping inputs on that box with no change to time delay behavior...it is shore power priority either way and delay on both legs.  The bottom box is inverter and all other A/C power.  When I am on battery power, the inverter takes 2 minutes to connect, as does generator (okay with that) and shore power.  2 minutes seems like hours when I want to start a pot of coffee off the inverter, and days when I plug into the pedestal and nothing happens for an eternity...2 minutes.  The inverter does do it's ATS thang when it is "on" and shore power drops off.

I run a Progressive PD-50ex pedestal connector to protect against polarity/current issues.  I want to be able to connect the inverter (Magnum 2812) instantly, and have the coach instantly accept power once the PD-50ex does it's safety checks...takes about 6 seconds.

I do not want to replace these units as they are working great ever since I cleaned and lubed the contacts on both boxes this last winter...no more hum and no buzzing during connect.  My only gripe is the time delay frustration.

Here's a pic of the top ATS connections if it helps identify any significant differences with y'all's configuration.  Woody

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Re: MagneTek ATS 100 Type 1 Time Delay hack. OEM 2001.

Reply #7 – October 14, 2022, 05:53:20 pm

My diagram is from 10 years ago and I don't want to rely only on the diagram.

I modified the diagram below to help you identify wires to bypass delay, but recommend that owning a Foretravel and not trying to follow a simple diagram and test circuits with a test meter can lead to ownership issues. 

The diagram indicates there is a yellow hot wire wire connected to the contactor relay screw terminal that energizes the contactor coil which closes the contactor points.  This wire voltage flows through the small square delay switch/relay.  Connecting the yellow wire directly to contactor coil should close contactor immediately when voltage is sensed.

Use your meter to be sure the wires are not hot before touching them

BTW,  it is important to re-tighten all the big screws holding down the big #6 wires.  A loose connection will always cause overheating and problems. 

The 6 separate points on these contactors are replaceable and could extend the life of this transfer switch box.  Often the center neutral points over heat, burn, discolor, etc. from more than 50 amps flowing on neutral circuits that are 120v instead of 240v.

Does not make sense that your shore / gen trans switch has a delay on both contactors.  How do you know that your generator does not have a built in delay and if your PD 50ex does not have a delay. 

Our ATS-100 is shore priority.  Also notice that the short output wires from inverter contactor are smaller, not 50-amp #6.  These wires join the output from shore contactor.

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Re: MagneTek ATS 100 Type 1 Time Delay hack. OEM 2001.

Reply #8 – March 04, 2024, 05:51:24 pm

Thank you Barry et al for the inputs.  After a couple of years of somehow tolerating the nuisance delay of my inverter engaging while dry camping (I leave it off unless needed for power), I decided to dive into eliminating the timer circuit so I don't have to stand next to the coffee pot in the morning like a zombie waiting for the ATS to kick in.

Both my ATS units are the Magnetec 100's with the time delay circuit.  The top box is Shore/Generator switch and the bottom box is Main/Inverter switch.  Biggest chore was removing the top unit and wood platform to access the guts in the lower unit. 

My wire colors are slightly different from Barry's diagram, typical for me, which complicated my lame AC electron logic.  After lots of head scratching I decided to pull connectors and reattach randomly.  Thankfully the first try was a success and no fire ensued, and so far haven't let the smoke out of any components.  Tested with the inverter, shore power and Powertech to make sure inverter was the lowest priority and kicked on instantly when initially powered up and performed it's APS function when all other power was removed.

Basically I removed the jumper from the Coil Hot to timer module, pulled the Inverter hot terminal off the timer module, and plugged it into the Coil Hot terminal.  In my ATS's this is a green wire.  Diagram attached for the fellow electron challenged folks.

As it turns out, my time delay for the shore power connection in my original post had nothing to do with the ATS, but is delayed by my Progressive Industries EMS PT50X.  If plugged directly into a power source, the ATS kicks on instantly.  Generator has the delay and shore power is highest priority.

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