Alright lets start this over. After getting spanked for a crappy multiple question rambling with terrible schematics to go with it, a few pointers of what I missed in the data sheets, I have a new plan and two questions.

Question one: Hopefully this schematic is a little clearer than the last ones, but will this work to replace the 3 wire 3-way rocker switch to automate the switching process of my PWM speed controller I am currently using to adjust both the strength and manually change direction of a magnetic solenoid?

And Question two: Does the PWM isolate the inductive load from the solenoid so I do not need to protect the relay from it in the switching wires as is shown in the inductive load wiring schematic in the third image linked or do I still have to wire it with the inductive load protection? And I guess as a second part to this question, if I do not need the inductive load protection, is it a good idea anyway to put a diode facing the PWM from the "switch" for safety of the relay should the PWM ever short out.

I apologize that the schematics symbols are still not completely correct and there was no option available to make the wires jump over in a non connection junction, so for all intents and purposes all crossing wires are not connected unless there is a dot. And the relay symbol does not show it but the relays do have a internal fly-back diode as shown in image 3 attached.

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Hall Sensor Link: https://sensing.honeywell.com/honeywell-sensing-103sr-series-hall-effect-position-sensor-sealed-housing-product-sheet-005971-1-en.pdf

SSR's DC60s3 and DC60s3-B Link: http://www.crydom.com/en/products/catalog/dc60-series-dc-panel-mount.pdf

Potentiometer/motor controller Link: https://www.amazon.com/uniquegoods-Upgraded-Controller-Reversible-Adjustable/dp/B01M26YWXZ/ref=sr_1_fkmr0_1?s=hi&ie=UTF8&qid=1517794790&sr=1-1-fkmr0&keywords=50v+reversible+bmw+motor+control

  • \$\begingroup\$ TL;DR. Are you operating with the specifications of the SSR? Do they have internal flyback diodes? Do you PWM them? How hot do they get? \$\endgroup\$ – winny Feb 5 '18 at 6:37
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    \$\begingroup\$ TL;DR - reduce your post to <20% of its current length. Find the one question you want to ask, and the evidence around that. Your entire first paragraph is waffle. I only got 50% the way through the second, before deciding that was waffle too, and gave up reading. I'm not going to sift through the rest, hoping something may be relevant. \$\endgroup\$ – Neil_UK Feb 5 '18 at 7:07
  • \$\begingroup\$ Should now that I am switching to limitable current bench supply, Was for sure my problem at one point but I cut the current way down and still popped a couple relays after running a bit. I am pretty sure that they do have flyback diodes, looks to me in the diagram like 3 pages into DC60S3 data link shows it does. I have tried both direct current from the battery and through a pwm controller for the output current, same result. Dead relay. Didn’t measure tempature but cannot feel any increase in tempature. I hear a pop, can smell it, and the solenoid sticks to a single polarity. \$\endgroup\$ – LonnyM Feb 5 '18 at 7:33
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    \$\begingroup\$ Add captions below your schematics to tell us what each one represents. The schematics are very difficult to follow due to the use of non-standard symbols and poor layout. Have a look for H-bridge schematics to see the standard configuration. I suspect that you have "shoot-through" when you reverse the motor. This means that you have a short-circuit between V+ and V- through the SSRs for an instant. Also, you have no component designations (SSR1, SSR2, etc.) so discussing the circuit will be very difficult. \$\endgroup\$ – Transistor Feb 5 '18 at 8:45
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    \$\begingroup\$ "I am pretty sure that they [SSRs] do have flyback diodes, ...". Yes but the wiring diagram on page 2 clearly states "Inductive loads must be diode suppresed" and shows how. \$\endgroup\$ – Transistor Feb 5 '18 at 8:52

It's looking a lot more sensible now.

  1. The speed controller link is to an Amazon page and there is no datasheet so you are guessing that the control inputs will work as you propose. Our standard advice is, "No datasheet - no sale." You have been warned.
  2. The SSRs are overkill for the control inputs and may have enough leakage current to cause problems. (I didn't check the datasheet.) Opto isolators would be better but you won't find a NC version.


simulate this circuit – Schematic created using CircuitLab

Figure 1. Basic scheme of direct and inverted opto-isolators.


Alright, I just went for it... It actually worked. I don't know that I would recommend this as a long lasting solution but it did work. The three wires for the three way are center ground and a positive to connect for each direction. Worked great for the mechanical testing purposes of the project. The PWM is a cheap Chinese piece of junk and uses electromechanical relays for the three way switch so it makes a bit of a racket. And in addition to the drawings I added diodes to exit side of the output to block any incoming current from the other side. Still coming up with a more permanent solution probably using an arduino board to interpret the hall signal and run a mosfet H bridge.


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