progressive dynamics power converter Model PD6921

[SusanP]

Hi folks - my new-to-me 1979 Trillium 4500 has a progressive dynamics power converter Model PD6921. I think that it has been damaged: see picture. The small square to the left of the plug (reads "green band means off/push on/pull off) seems broken to me. Anybody seen this before? Can it be fixed? Can I keep using this, or must it be replaced? Thanks!

[Mike Meyer]

Originally Posted by SusanP

Hi folks - my new-to-me 1979 Trillium 4500 has a progressive dynamics power converter Model PD6921. I think that it has been damaged: see picture. The small square to the left of the plug (reads "green band means off/push on/pull off) seems broken to me. Anybody seen this before? Can it be fixed? Can I keep using this, or must it be replaced? Thanks!

I suspect that is the 120V circuit breaker and the top has been broken off. The good news is that it can likely be replaced. UHaul used similar devices. These are similar to what are used on small airplanes. Search for 10 A push button reset circuit breaker on Amazon and compare pictures to see if compatible. You will have to take the cover off so make sure that you unplug everything.

[SusanP]

Hi Mike - thanks for commenting. There is a button on the right-hand side that reads "12 volt output," a min-breaker. It seems to work fine. Like you, I also think something has broken off the button on the left-hand side. I'll be sad if I have to replace the whole unit because of that!

[gordon2]

See this thread: https://www.fiberglassrv.com/forums/...ter-51997.html

It appears that it is a single stage charger.. if it is, and if it were me, I would surely replace it with a modern multi-stage charger / converter.. even if it was not broken.

[John in Michigan]

(EDIT: I am surprised your converter works at all. Definitely don't use it to charge a battery.)

I have this same unit on my Trillium 4500. The problem with replacing the original converter with a modern one is that there is very little space in that location, less than 4" depth. I found one solution that fits, the Parallax 80D Distribution Panel with a separate converter charger such as a Progressive Dynamics PD9245C converter charger to be located in adjacent space.

Another option is to relocate everything to the adjacent space where the shore power cord is stored. This would give you the option of other converters. Either way, you would also want to upgrade to 30 amp shore power. This would also allow you to have at least two AC branch circuits instead of one, a great benefit if you run more than one high amperage AC appliance.

I plan to upgrade at some point, but meanwhile I have replaced the AC push button circuit breaker with a 15 amp push button circuit breaker. Why? Because it protects the (EDIT: the wiring for the) entire power load in this unit including:

- FOUR AC outlets (one on the converter, two others inside the camper, one in the fridge cabinet)
- The AC/DC transformer providing power to DC circuits (several lights)

I also replaced the DC push button circuit breaker with a 10 amp push button circuit breaker. Also replaced the toggle switch. Also replaced the transformer with a 15 amp 12 VDC power supply. I use a separate smart charger to charge the battery.

[thrifty bill]

IMO, those old power centers were garbage, and get worse with age. Start looking for a replacement. With my 1300, there was plenty of room. But others report limited space in the 4500. Time for research.

I went with a 30A system.

[Capn.Curt.Wiebe]

We also have an old 4500, and had the same problem.

Since we do NOT have air conditioning or onboard batteries, I just went to a local electronics supply store and bought the closest replacement piece that I could find. Works great and just cost a few bucks.

If you don't need it, I would not recommend upgrading. If you are going to install batteries and/or air conditioning, then it probably would be a good idea.

[David Tilston]

The original PD6921 is strictly for your 12VDC lights. It is not a battery charger. If you try to use it for that you will boil your battery dry. In fact, if hooked up correctly, it only connects to the battery as an alternative 12VDC source, when no 120VDC is available.

My favorite replacement would be a Progressive Dynamics 4600:
https://www.progressivedyn.com/rv/po...r-4600-series/
This is meant as an upgrade for older power centers, but can be adapted to the hole for the PD6920, as in this post:
https://www.fiberglassrv.com/forums/...tml#post325467
I like the use of the cold air return duct cover.

It comes with a DC distribution/fuse board, (see picture) which you can plug in the . This would need some mounting hardware to make it a finished product like this:
https://www.progressivedyn.com/rv/ac...ibution-panel/

[Steve Hague]

Our 1978 Trillium 4500 also has the PD 6921 power converter. It was only sending power to the LED lights and seemed to function well.
We recently installed a Maxxfan 5100K. It works well on battery power, but shuts down quickly when the converter is providing the power.
I read somewhere that the Maxxfan will not tolerate more than 13.8 volts.
So, I checked the voltage at the fan power input. On battery it read 13.4 volts, when switched to converter it read 20.1 volts.
Sounds like I need to replace the old converter. I was already planning to replace it, but wasn't happy about the selection of new units that would fit in the space. May need to relocate the converter to under one side of the double bed.
Any other suggestions?

[John in Michigan]

Steve, I was able to squeeze a PD5000 power distribution panel into the existing Trillium 4500 converter space below the furnace. Its about the only device that fits and its just a good quality AC DC power distribution center, i.e., it doesn't include a converter circuit. Instead you would select a separate deck mount converter that plugs into the back of the PD5000. Nice thing about the PD5000 is that it has screw terminals (or optionally 1/4" spade terminals) for each 12 vdc circuit AND a separate 12vdc negative bus. The PD4135 simply has a pigtail wire for each 12 vdc circuit and NO 12vdc negative bus.

Instead of using a deck mount converter, I used a smart battery charger permanently plugged into an agm battery under the driver's side rear bench. Or if you don't use a battery, you could just plug in a 12 vdc power supply.

[Steve Hague]

Thanks John. Lots to ponder.
Since our power needs are small at this time, wondering if we need the converter function at all. We have a smart battery charger connected to AC next to lead acid battery under front bunk. The battery runs power for refrigerator circuit board and refrigerator fans directly (5A fused). Power for lights and fan run through the PD 6921 and utilize its 12v circuit breaker.
Wondering if I could just disconnect power to the converter internally and continue to utilize the existing PD 6921 as a simple power distribution panel until our power needs demand something more sophisticated?

[John in Michigan]

Yes, you can get by with existing equipment as long as:

- all AC and DC wiring is fuse or breaker protected
- the smart charger output amperage is sufficient to cover loads

We used the original 6912 converter for several years after replacing both the AC and DC circuit breaker and removing the transformer and using a dc power supply instead, but could have used a smart charger instead.

When we ultimately replaced the 6912 converter with a PD5000 power panel, this provided:

- 30 amp shore power which could simultaneously power more AC appliances on multiple AC circuits, which is good IF you actually want this feature
- option of either a deck mount converter/charger, a smart charger or a DC power supply for the DC side

To me, if you only have 5 or 10 amps of DC loads why bother installing a converter/charger?

[Steve Hague]

I snipped the AC power input to the converter coil (see pictures), but left the AC and DC circuit breaker circuits intact. Now I don't need to worry about burning out the Maxxfan control board.
As to the stand alone battery charger, it has only a 1.5 A output, so I'm looking to replace it. Our total DC should typically be in the 1 to 5 Amp range, but thinking of looking for a smart charger around 10 Amp.
Any suggestions?

[John in Michigan]

This 10 amp smart charger has these features:

- can select various lead acid type batteries or lifepo4 battery
- can select 12v power supply mode to power any 12 vdc device (without a battery)

[Steve Hague]

I don't see a link or product name. Sounds like something that would fit our needs from your description.

[John in Michigan]

link to 10 amp charger:

https://www.amazon.com/NOCO-GENIUS10...7W3QT226&psc=1

[Steve Hague]

This 10 amp smart charger looks promising. We are camping next few days on current setup and see how it goes.

[TODD KLIETZ]

Hi all - we've had our 4500 for years but the only thing I've used the battery for is to power our cabin lights which I've replaced with led light panels. All is fine with using it for those lights although this weekend I plugged my phone charger directly into the 110 outlet of the power converter thinking that I should be able to charge my phone from it - but no joy. None of the other outlets would charge my phone either. Is that "normal" for these PD6921s?

[David Tilston]

Originally Posted by TODD KLIETZ

Hi all - we've had our 4500 for years but the only thing I've used the battery for is to power our cabin lights which I've replaced with led light panels. All is fine with using it for those lights although this weekend I plugged my phone charger directly into the 110 outlet of the power converter thinking that I should be able to charge my phone from it - but no joy. None of the other outlets would charge my phone either. Is that "normal" for these PD6921s?

Todd, The converter on a Trillium 4500 is not an inverter. It is used to convert 120VAC to 12VDC. When the trailer is plugged in, the converter can pass 10A at 120VAC through to the plug on the front. However there is a small pushbutton breaker that may have popped. To reset, push the button.

[Jamie June]

David Tilston, I am looking for some kind of replacement for the old original Progressive Dynamics Solid State that came in my 1978 and would love to be able to put it in the same hole. The forum you link to below to show someone doing that won't come up for me, is the page still there? I got a battery and some solar components but before I get complicated I just want to get the lights going in there and see if the wires are OK and stuff. I don't really follow some of this since as you point out the old converters won't charge a battery, yet most of the trilliums lights work off the battery. So was the battery supposed to charge through the tow vehicle connection or ?

Originally Posted by David Tilston

The original PD6921 is strictly for your 12VDC lights. It is not a battery charger. If you try to use it for that you will boil your battery dry. In fact, if hooked up correctly, it only connects to the battery as an alternative 12VDC source, when no 120VDC is available.

My favorite replacement would be a Progressive Dynamics 4600:
https://www.progressivedyn.com/rv/po...r-4600-series/
This is meant as an upgrade for older power centers, but can be adapted to the hole for the PD6920, as in this post:
https://www.fiberglassrv.com/forums/...tml#post325467
I like the use of the cold air return duct cover.

It comes with a DC distribution/fuse board, (see picture) which you can plug in the . This would need some mounting hardware to make it a finished product like this:
https://www.progressivedyn.com/rv/ac...ibution-panel/