Reciprocating autuator with time delay at extremes of stroke (required wiring)
Reciprocating autuator with time delay at extremes of stroke (required wiring)
(OP)
Hi all,
I'm currently designing a system which requires a electronic linear actuator on a reciprocating cycle. I have been informed it would be relatively easy to use a latching DPDT relay with 2 micro switches positioned at each end of the actuator's stroke. However, I require a time delay at each end of the stroke so the actuator remains at full stroke / zero stroke for 2 / 3 seconds before moving in the opposite direction.
Can anyone help me with this one?
Cheers,
Joe.
I'm currently designing a system which requires a electronic linear actuator on a reciprocating cycle. I have been informed it would be relatively easy to use a latching DPDT relay with 2 micro switches positioned at each end of the actuator's stroke. However, I require a time delay at each end of the stroke so the actuator remains at full stroke / zero stroke for 2 / 3 seconds before moving in the opposite direction.
Can anyone help me with this one?
Cheers,
Joe.





RE: Reciprocating autuator with time delay at extremes of stroke (required wiring)
I use the Siemens LOGO! for that. Lots of examples in the application libraries if you are unsure how to implement your function. There's probably also a User Group that can help you.
Gunnar Englund
www.gke.org
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Half full - Half empty? I don't mind. It's what in it that counts.
RE: Reciprocating autuator with time delay at extremes of stroke (required wiring)
Bill
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"Why not the best?"
Jimmy Carter
RE: Reciprocating autuator with time delay at extremes of stroke (required wiring)
RE: Reciprocating autuator with time delay at extremes of stroke (required wiring)
Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.
RE: Reciprocating autuator with time delay at extremes of stroke (required wiring)
Keith Cress
kcress - http://www.flaminsystems.com
RE: Reciprocating autuator with time delay at extremes of stroke (required wiring)
RE: Reciprocating autuator with time delay at extremes of stroke (required wiring)
Keith Cress
kcress - http://www.flaminsystems.com
RE: Reciprocating autuator with time delay at extremes of stroke (required wiring)
A pre-programmed spare unit should be available if the machinery is critical. If not so critical, then wait till someone can fix the system comes along.
Finding lose wires and failing limit switches is something an electrician should be able to do. The relay as such seldom fails.
Do electricians shy away from PLCs?
Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.
RE: Reciprocating autuator with time delay at extremes of stroke (required wiring)
I think needing a PLC where two timing relays would work might be on the verge of over-kill. Now if more tasks can be found to use the PLC for...
Keith Cress
kcress - http://www.flaminsystems.com
RE: Reciprocating autuator with time delay at extremes of stroke (required wiring)
Skogs - Yes, some do. It depends on the industry. The lads at my previous employer (power generation industry) would have had no problem. Where I am now (in the oil industry) the electricians have yet to discover the circular wheel.
RE: Reciprocating autuator with time delay at extremes of stroke (required wiring)
Some have different model numbers for different functions, so the replacement would only have a dial or switches for the time setting.
Here are examples.
http://www.kele.com/relays-and-contactors/821td10h...
http://www.kele.com/relays-and-contactors/rte-seri...
http://www.kele.com/relays-and-contactors/438usa,-...
Disclosure: I am on contract with Kele, and was chief engineer for many years there. The relay(s) shown are available many other places.
Best to you,
Goober Dave
Haven't see the forum policies? Do so now: Forum Policies
RE: Reciprocating autuator with time delay at extremes of stroke (required wiring)
Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.
RE: Reciprocating autuator with time delay at extremes of stroke (required wiring)
RE: Reciprocating autuator with time delay at extremes of stroke (required wiring)
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Reciprocating autuator with time delay at extremes of stroke (required wiring)
I have done some work in the UK. On one site, there was a guy working on a manual lathe producing little pins with chamfers at both ends and two grooves for retaining rings. On another site, there was a paper machine with drives from late sixties up to modern days. There was a "slight" problem with the speed setpoint chain and also with drives being of so differing character - old DC drives via old scalar drives to modern vector drives - that it was almost impossible to change speed with out having a web brake.
My remarks that it might be a good idea to do something about both these situations were not received well. Charming, in a way. But a problem.
I can understand that a programmable relay, how good and reliable and easy to replace it ever may be, can be looked upon with the deepest doubt in some locations. I still maintain that it is a good and simple way of getting the work done.
Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.