Can Williams "True Blast Plus" Locos Operate on DC Power

I would think it would not be an issue. The motors are DC, The Williams 6Amp board converts AC to DC power. The True Blast is plugged into the 6 Amp board. So it too would also operate on DC power.

Doug

From the Bachmann (Williams) website.

I think it will work. When you pass DC through an AC to DC bridge it lowers the output voltage by 1.5 volts which will slow the engine a bit more. Should be fine.

Rob

The locomotive itself will operate on DC, it doesn't care. The 'True Blast' sound board does, since the DC from the transforer is what triggers either the horn or bell when you press the appropriate button.

On the 6 amp reverse board there are two 2-pin connectors. One is a DC output that was intended for connecting a tether to a second locomotive.

The second 2-pin connector passes AC straight through from the track pick-ups. This is the one the 'True Blast' sound unit connects to. When it detects the +/- horn/bell DC voltage on top of the track AC, it triggers.

If you want to operate the loco on DC, you have to unplug the sound board from the reverse unit.

Thanks Len2,

That confirms what I thought would be the case from my limited knowledge of AC trains picked up when I was in "S" scale (DC), but I wasn't certain. Am I correct in thinking that the difference between the bell and horn button is that one applies DC+ to the center rail and the other applies DC-? 

I guess I'll have to budget for a decent AC power pack. In the meantime, I'll just have to run on the club's modules using their power (least my wife won't have to put up with me setting up track on the living room floor, for a while, anyway!).

Bill in FtL

Yes, DC+ triggers the horn, DC- the bell.

Almost forgot! It wasn't a planned use, but I've found using the 2-pin DC tether connection for installing a directional lighting circuit very handy. It's output swiches polarity with the motor outputs when direction is changed, meaning all that's needed is a couple of current limiting resistors and LED's to install basic directional LED headlights. A little more circuitry, and you get constant brightness too.

Running the loco on DC through the DCRU board......will it not run one direction only??? Or will a power cut flip polarity?? Just wondering.

No, you still have directional control. The newer reverse board on Williams locos are basically just a "brain" IC, a pair of full wave rectifiers feeding a couple of DPDT relays that in turn feed the motors. When power is cut, then restored, the "brain" tells the relays to flip, reversing the power to the motors. All that happens when you use DC, instead of AC, for power is you lose a bit of voltage through the rectifiers.

I will second what Len2 mentions about the Williams True Blast 2 units.

The True Blast 2 unit will continually sound off in DC voltage.

The motors are DC but the True Blast 2 needs AC with a DC pulse or something like that to function.

Lee Fritz

LEN2  has is right.    will run, but you lose the bell + whistle function as one or the other will sound continually unless the board is un-plugged

I wasn't aware of the LionChief AC/DC acceptance.

WBB's instructions (above) hint otherwise.

All the instructions that I have seen on my 3RO locos - many locos, many brands - have

been clear about "running your new XYZ loco on DC will damage the electronics". But

I no longer read the "basics" in instructions, and most of my purchases are

used locos. 

The above advice about "the motors are DC..." is dangerous - it's the boards that may be

harmed by the DC, not the motors. Electronics expecting AC will be toast if you give them 

DC.

Having DC motors ensures nothing per the boards.

Having said all that, some electronics are now indeed capable of properly processing

either AC or DC; is your loco so equipped?

Bachmann knows; we don't.  

Williams E units use relays, not triacs or FETs. The first component connected to track voltage is the bridge rectifier. AC passes through both halves of the bridge alternately. DC just passes through one leg of the bridge.  After the bridge its all DC Which passes through one of the relays to the motor. The motor sees only a straight DC voltage proportional to the AC track voltage. The flip flop still switches the relays when track voltage approaches zero and the DC to the motor is reversed.

Triac E units apply Pulse Width Modulated DC to the motors. AC is required to trigger the triacs. You can't run a Lionel engine with their electronic E units on DC but you can use DC with Williams and Bachmann.

Pete

You must not own any MTH PS2 or PS3 stuff.  All the 3V PS/2 and all PS/3 boards run on either AC or DC.

Actually, you can. As with WBB, the entire device works on DC(reversing and motors) and is powered by a rectifier matrix arranged to form a full wave bridge as the first set of components on the board wired to the AC input. I have run a couple of RS-3s and K-Line MP-15s very satisfactorily on DC with MRC power packs.

K.-Line used relays. Not sure what RS3 you are referring to.

Pete

No relays in any of my K-Line diesels.

RS-3s are Lionel... Amtrak & NYC.

This isn't true either.  Triacs are diodes that can pass current either direction hence work with AC, but they also work with DC.  In fact I believe the DCDR uses the same Triac as the ACDR.    G