dc/dc ssr problem

Discussion in 'General Electronics Chat' started by kwhkwh, Aug 9, 2016.

  1. kwhkwh

    Thread Starter Member

    Jul 19, 2016
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    should there be output voltage on a dc/dc ssr without input voltage thanks,,,kev
     
  2. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Show circuit!
    Max.
     
  3. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    See off state leakage in the datasheet..
     
  4. bertus

    Administrator

    Apr 5, 2008
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    Hello,

    What is the partnumber of the DC/DC SSR that you are using?
    In the attached datasheet there is the "off state leakage current" given of max 1μA.

    Bertus
     
  5. kwhkwh

    Thread Starter Member

    Jul 19, 2016
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    hi al,l I have used a fotek dc/dc 100 amp output from ebay, with a max 40 amp output pwm, I supplied 9v to the pwm and connected output to ssr input ,I then connected a small dc motor to output of ssr using 9v supply and a blocking diode without turning on pwm, the motor ran, I disconnected pwm and still the motor ran. I then connected my mutimeter to out of ssr and it showed zero. could the ssr be faulty. I tested the pwm with the 9v motor on its own and it works great, but I wanted the ssr to control a high current heater thanks for any help... great site...kev
     
  6. bertus

    Administrator

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  7. MaxHeadRoom

    Expert

    Jul 18, 2013
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    I don't see any DC-DC Fotek SSR's on ebay, do you have a link, are you PM'ing the input??
    Max.
     
  8. kwhkwh

    Thread Starter Member

    Jul 19, 2016
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    hi I bought a 40a max pwm works fine I then bought a fotek 100a dc/dc ssr off ebay I connected 9v to input of pwm and output to input of ssr ,output of ssr to small dc motor with 9v supply including diode. without imput from pwm motor ran when 9v applied disconnected pwm completely motor still ran could it be a faulty ssr...thanks kev
     
  9. bertus

    Administrator

    Apr 5, 2008
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    Hello,

    The SSR is likely a DC/AC relays.
    It will not turn off with DC.

    As said before, Give us a link to the used SSR.

    Bertus
     
  10. MaxHeadRoom

    Expert

    Jul 18, 2013
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    I don't get how you are configuring PWM to a SSR??
    What are the details of the PWM.
    Why introduce a SSR?
    Is this one of the Ebay $5.00 specials?
    Max.
     
  11. kwhkwh

    Thread Starter Member

    Jul 19, 2016
    33
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    hi thanks I cant find a link but it is advertised on ebay uk as bgbulkdl7 and yes I am using pwm on input of ssr thanks again
     
  12. kwhkwh

    Thread Starter Member

    Jul 19, 2016
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    hi cant find a link but is selling as dc/dc ssr on ebay uk
     
  13. kwhkwh

    Thread Starter Member

    Jul 19, 2016
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    hi I wanted to use the ssr as a high current pwm controlled supply to a dc heater and yes it is a £7 unit
     
  14. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Show how you have it hooked up, the motor should not run without any input on the SSR.
    What voltage is the heater?
    Max.
     
  15. kwhkwh

    Thread Starter Member

    Jul 19, 2016
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  16. kwhkwh

    Thread Starter Member

    Jul 19, 2016
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    I connected a 9v + supply to the ssr output I then connected the - supply to the motor and then from the othe motor connection to the negative out put of the ssr including a back emf diode across the motor . without input from the pwm the motor ran at full revs? thanks
     
  17. kwhkwh

    Thread Starter Member

    Jul 19, 2016
    33
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    the heater is approx. 13v I used a small dc motor to test the ssr before running a high current through the ssr
     
  18. MaxHeadRoom

    Expert

    Jul 18, 2013
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    A SSR with no input the output should normally be OFF, .
    Max.
     
  19. kwhkwh

    Thread Starter Member

    Jul 19, 2016
    33
    0
    thank you this why I think the unit is faulty do you agree thanks for your time
     
  20. kwhkwh

    Thread Starter Member

    Jul 19, 2016
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