Dc controller output vdc lower than input vdc

[Santas Helper]

I opened a ticket with LOR but thought I would ask the general public here.

 

I'm having an issue where my DC controllers are putting out lower volts than what I providing the board.

My input power 11.6vdc. All the channels are putting out 10vdc. This is a brand new controller.

 

On another board I have 17.6vdc going in and  about 9.6vdc going out to all channels. This controller is a couple years old.

 

I never really checked the out put of my DC controllers before (didn't have a need) so the lower voltage might be normal? (that doesn't sound right to me)

 

I was trying to dial in my LED floods with correct resistors while modifying them but this lower voltage is messin with my resistor choice as to what I should be using.

 

Anybody run in to this?

 

Thanks,

Tom

Edited September 19, 2013 by Santas Helper

[plasmadrive]

I have some of the LOR DC controllers that I have yet to fire up.. but there will be some voltage drop.  Depends on how many amps you are drawing and a couple of other things.

 

First, where are you measuring the voltage?  Right at the controller or the end of the wire at your lights?  The wire will drop some as well.

 

Second, how are you driving the controllers?  If it is with S3 make sure you have the intensity set to full.  I know that sounds simple but it could be an easy over sight, have to ask.

 

The one that would concern me the most is the older one. That seems like one heck of a voltage drop.   If you are drawing any kind of current those heatsinks should be pretty hot.

[Santas Helper]

Here is the thing. I unplugged all lights. I was just testing two LED floods when first checking.

So with all channels empty (no lights) I rechecked.

I'm not using S3 (using 2.9) and all channels are at 100%

 

With no load at all, I am getting the above (first post) figures.

[plasmadrive]

Something ain't right for sure.  S2.9 won't make any difference.  I have never tried to trace down the LOR circuit but I assume it is a bunch of MOSFETs driving by the rest of the circuit "stuff".  Given that case, there should be almost no drop. 

 

Very strange indeed. 

 

Just for yucks and grins.. perhaps see what AC component is there and if there is any at all.  The older controller is loosing about 1/2 its input.. that sounds like input power supply issues perhaps.  I don't know.. but checking for AC might not hurt.

[Santas Helper]

 I don't know.. but checking for AC might not hurt.

What do you mean checking for AC"?

AC component?

[plasmadrive]

just put your meter on the AC voltage setting and look at what is supposed to be just DC both input then output of the controller.

[Max-Paul]

I would also check all connections, to include the wire from the PS to card terminals, any connections on fuses. Also solder joints at the VDC input terminals and fuse holders.

I could ALMOST expect the 1.6vdc drop, but expect more like .6vdc drop. But the almost half of supplied voltage drop is major wrong. And I am with Plasma. When your filtering caps go bad on a cheap P.S. or any priced P.S. The D.C. voltage will drop but the A.C. component riding on the DC will increase. Even so, would only expect that to drop to the RMS value.  BTW with the power supply leads removed from the card. What is the measured voltage on the P.S.? might be the power supply. Fastest way to trouble shoot is to divide and conquer.

[-klb-]

Also, don't measure the output without a load.  Put some load on it.  The key measurement is voltage from - in to - out on a channel. + in to + out should always be around 0.  Anything else indicates a bad connection.  The - in to - out should be a fraction of a volt.

[Ken Benedict]

What is the size of the DC wire?

 

Might be chocking on small gage wire.

[Santas Helper]

Thanks for the ideas guys. I got busy last night and could proceed with further checks.

I attempt it this weekend and let you know.

[LORisAwesome]

Does the DC controller have a max intensity setting like the AC controllers do?  Could it be set lower than 100%?

 

Just a thought...

 

Jerry