Stock D'lite relay supply and 4 relays

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greiswig
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Stock D'lite relay supply and 4 relays

Post by greiswig »

I know, it's odd. The stock amp only had 2 relays, and now I'm trying to run 4. It works fine with the switches on the amp, but if I use the footswitch (yellow LED in series, not a dead short as in the switches), if I have 2 of the relays tripped already through the red LED, the other relays won't trip. The other way (Yellow LED/relays tripped, then trying to trip the other two) works fine.

It seems like there should be more than enough current to keep up with this demand, but the voltage drop at the coil is substantial as more relays get tripped, going from 12V with all open to under 5 with all closed.

I also know that the LED is limiting current, which probably isn't helping. But is there something relatively easy I could do to this circuit to get this to operate properly, or do I have to do FWB rectifier/regulator? Circuit is as depicted at https://tubeamparchive.com/download/file.php?id=1663

Thank you!
-g
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heisthl
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Re: Stock D'lite relay supply and 4 relays

Post by heisthl »

scrap the voltage doubler and switch to 5 volt relays (if it could run 2 with the doubler, it can run 4 without).
Former owner of Music Mechanix
www.RedPlateAmps.com
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greiswig
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Re: Stock D'lite relay supply and 4 relays

Post by greiswig »

heisthl wrote:scrap the voltage doubler and switch to 5 volt relays (if it could run 2 with the doubler, it can run 4 without).
So just converting it to a half-wave rectifier would be easy...is that what you're saying? I've got 5v relays I can use already.
-g
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Bob-I
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Re: Stock D'lite relay supply and 4 relays

Post by Bob-I »

I had this problem with an amp with 3 relays. Turned out the LEDs were dropping voltage despite having enough current supply.

The fix was to use a seperate line off another node in the relay supply, to the footswitch with voltage the the LEDs and a DPDT switch, One side of the DPDT switch switches the relay, the other side switches the LED on. This way, the seperate node does't drop voltage across the LEDs. I just added one 1000uF cap and a 100 ohm resistor.

If you don't like this idea I'd try the relay supply like on the ODS102 schematics posted in the files section. I don't know if it'll work with 4 relays but it's rock solid with 2.
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heisthl
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Re: Stock D'lite relay supply and 4 relays

Post by heisthl »

greiswig wrote: So just converting it to a half-wave rectifier would be easy...is that what you're saying? I've got 5v relays I can use already.
Use a full wave bridge - the 5 volt tap will yield a little over 7 volts which gives you some leeway on series LED dropping.
Former owner of Music Mechanix
www.RedPlateAmps.com
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Structo
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Re: Stock D'lite relay supply and 4 relays

Post by Structo »

I use a 8v regulated supply.

The relays are the Omron 5v ultra sensitive.
Then again I am only using two relays but I had planned initially to use three.

In my case I ended up using a 5 pin DIN connector.
One wire supplies voltage to the LED's so that they don't load down the relay coils.

Also different colored LED's draw different amount of current.
With red being the lowest I think.
So for 4 relays I believe you would need 6 conductors and connectors.
Tom

Don't let that smoke out!
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greiswig
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Re: Stock D'lite relay supply and 4 relays

Post by greiswig »

heisthl wrote:
greiswig wrote: So just converting it to a half-wave rectifier would be easy...is that what you're saying? I've got 5v relays I can use already.
Use a full wave bridge - the 5 volt tap will yield a little over 7 volts which gives you some leeway on series LED dropping.
That did it. Perfectly reliable switching now. Thanks!
-g
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