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PEC autostart control circuit

PEC autostart control circuit

PEC autostart control circuit


Can anyone help me with a PEC autostart control circuit.
Basically I have two conveyors (3ph sc motors) Once manually stared, they should both stop start according to the one PEC's requirment, stop when the beam is broken and start when the object is removed and stop completely if an e stop is pressed.


RE: PEC autostart control circuit


RE: PEC autostart control circuit

PEC, Photo electric cell, A photo beam sensor if you like, that switches when the light reflected between the sensor and a simple reflector is interupted.
Sometimes type NPN, but this one can switch up 240v 100mA, Dp, NC/NO.
I hope this helps to explain the situation.

Thank you.

RE: PEC autostart control circuit

Are you too cheap to hire an engineer or go to a control panel builder? This is what we do FOR A LIVING. For professionals, this is a 10 minute job (I am being generous I know), but what if we told you something without knowing all the details and someone got hurt? Would that stop you (or your lawyer) from hunting us down? I doubt it.

Free advice is one thing. Free design is another.

All that said, here is your solution (I just can't help it, I'm born to solve). But think of this kinda like weed: the first one is free, after that your gonna hafta pay buddy!

Series the estop with a 3 wire start-stop to a relay R1, using a NO contact of R1 as the seal in. Paralell to the relay but series to the estop, energize relay R2 with the PEC when an object is present (experiment with the PEC logic if you don't know it). Series another rung from the estop and energize both motor starters through R1 NO and R2 NC. Don't foprget the OL relays for the motor starters in there. I would put them (2 NC contacts in series) in the rung with R1 coil, requiring a manual restart after resetting an overload, but that's just my preference. You could also have them in the starter coil circuit, just remeber that the conveyors will restart as soon as you reset an OL.

With the estop made, hit the start button. Relay R1 energizes and seals in, staying energized until you hit stop, estop or the power fails (prevents automatic restart after a power failure for safety). Relay R1 energizes motor starters through R2 NC contact and runs conveyors until object hits photo eye. When beam is broken, R2 energizes and opens up NC contact in starter rung, dropping out starters until object is removed. When object is removed, R2 drops out again and since R1 is still energized, the motors restart.

If you did not understand that, you are not qualified to receive free design work and will need to gouge out your eyes as punishment for being an infidel looking upon the holy words of Control Logic. Or go hire someone who knows what they are doing.

This is offered as free advice only and has not been thoroughly investigated beyond the poster's published message. Use of this information is at your own risk. See what you forced me to type? Legaleze BS.

Subvert the dominant paradigm... Think first, then act!

RE: PEC autostart control circuit

jraef — Agreed.  'Flag' substantiation here was "…operational safety aspects will require inappropriate bandwidth for description… proposed controller… “hookup” is not… apparent, …no business dealing with the application…”  [Are we on the same plane?]

RE: PEC autostart control circuit

Suggestion: Essentially, there are sensors controlling motor starters. Some catalogs show the motor starter circuits. Then, one has to be familiar with the starter control circuits or PLC programming, if PLCs are applied.

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