Problem with Fragrance/vac combo

[SoapitUp]

Hi all , long time lurker , first time poster ! I am having a problem with my Fragramatics fragrance/vac combo , and need a little help zeroing in on the problem . It started out with the vac option quit working completely , I figured that the brushes had gone out in both motors after checking to make sure the fuses were not blown . (It did seem odd that both motors at the same time though) I also noticed that the windings were discolored and the stator was loose fitting (maybe a bearing?) on one of the motors , so I pulled both motors , discarded the obviously ruined one , changed the brushes on the remaining one and another used one I had on hand. I bench tested both of the motors that I had just put brushes in and they worked fine . After installing the motors back in the vac , they would not turn on . I tested the solid state relay , with the vac turned on and the only wire that had current was the one coming into the relay from the power box , the other three had no current . Could the relay be bad ? or the vac/fragrance switch bad ? Seems od to me that the wires that switch the relay on tho allow current through the contacts to the motors had no power . Would the problem be upstream on the switch side of the relay ? I ran out of time to troubleshoot the problem and didn't get a chance to jumper across the power-in to power-out terminals on the relay to the motors to eliminate that side of the relay as the culprit . Any suggestions or ideas as to where the problem is ? I downloaded a schemematic of the vac to check things out more indepth tomorrow , any help would be appriciated .

Terry

 

[MEP001]

Using your volt meter, test between hot and common. Start with the input to the relay, then the output. If you have power in and out, test between the two 24V leads that trigger the relay. You may not be getting that signal.

 

[SoapitUp]

Maybe I'm having a mental block or something , I don't quite understand your post . Here's what I've already tested , I grounded the black lead on my voltmeter to the case of the vac , then used the red lead to probe the terminals of the relay . With the vac on and the switch on the vac function , I get 120v from the power box to the relay (wiring that actually powers the motors) , 0v from the output that goes to the fuses/vac motors (indicating to me the relay is not closed) . No indication of any power on the switch side of the relay , on either terminal .

Every other function of the unit works , fragrance pump , LED readout , lights , coin acceptor ect. , but vac function does not .

Thank you for your responce , it is appriciated .

Terry

 

[MEP001]

Then it doesn't sound like the relay. It's probably just the vac/fragrance switch. You can confirm easily by jumpering with a piece of wire right at the switch.

 

[captain cw]

That relay has a nasty tendency to go bad. I replaced mine with real contactors. no problems since.

 

[SoapitUp]

Thanks for the responses guys , I didn't get a chance to troubleshoot the vac today , hopefully tomorrow , I'll let you know what I find .

Terry

 

[jwilson]

How old is your vacuum? Troubleshooting the solid state relay will be slightly different depending on the year.

 

[MEP001]

How old is your vacuum? Troubleshooting the solid state relay will be slightly different depending on the year.

How do you figure? If there's 24V to the relay and no 120V out, it's bad, same as any other relay.

 

[SoapitUp]

I think it's a 1997 model , that's when we built the wash and it was new . I stated that it was a solid state relay from looking at a schematic that I downloaded off of Fragramatic's website , there was two different ones for this model and I downloaded the older one . It does look like the wiring on my unit , as far as the componets . I have yet to troubleshoot the vac , hope to tomorrow .

Terry

 

[MEP001]

I have to say the earlier suggestion of replacing the relay with something better is a good one. I use mercury displacement relays in vacs now, and they rarely fail. I get the ones rated to 35 amps from Kleen-Rite for about $40, half the cost of the solid-state relay from Fragramatics, and it doesn't require a heat sink. If you do like the solid state model and want to keep the unit as original as possible, you can get the very same relay from Mouser.com for about $40.

 

[jwilson]

How do you figure? If there's 24V to the relay and no 120V out, it's bad, same as any other relay.

Our newer models have 5VDC on the switch side of the SSR. I stated this in case he checked the switch side and found that is was 5VDC instead of 24VAC.

Not all of the units with 24VAC are referenced to Earth Ground (the chassis). For the best measurement he needs to check between the two posts on the relay to assure that the return signal is there also, instead of checking between the post and chassis.

 

[SoapitUp]

Sorry about not getting back to this thread in a few days , but I did find the problem and fixed the vac . In troubleshooting the vac again , I checked the voltage again with the case ground method and still had no voltage on the switch side of the relay , after going through all the wiring on the whole vac , it occurred to me to check across the switch side terminals . Just as JWilson commented , it was not referenced to earth ground , I got 24v across the switch terminals , so relay no good , ordered relay and installed today , back up and going ! Thanks for all the help guys .

Thanks again,
Terry