AC Coil Operation
AC Coil Operation
(OP)
Just need some advice:
Have a customer who wants to operate a Coil in an extreme input voltage range (13 VAC to 190 VAC ). The design must have no DC or caps in it. Any ideas, a multi-stage coil design via a relay/resistor arrangment?
Have a customer who wants to operate a Coil in an extreme input voltage range (13 VAC to 190 VAC ). The design must have no DC or caps in it. Any ideas, a multi-stage coil design via a relay/resistor arrangment?






RE: AC Coil Operation
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: AC Coil Operation
Does it have to pull-in at 13vac or just not drop out at 13vac
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RE: AC Coil Operation
RE: AC Coil Operation
You may also use a thermistor (PTC) to reduce current after the initial high current. Google "PTC applications" for more info on that.
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: AC Coil Operation
RE: AC Coil Operation
Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: AC Coil Operation
What does "mon." means?
What does the solenoid do? Move something? 4 cycles seems like a very short energization time for solenoid.
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RE: AC Coil Operation
I would not give a PTC as big a chance as an ice cube in hell.. As that's what you'd be talking.
Remember at 190VAC you are talking about.. ah gesh..
If it is a 20W coil.
20W = 132 x R
R = 0.118 Ohms
At 190VAC you are talking P = 1902 x 0.118
P = 4.2kW
Or I = V/R
I = 1,600 AMPS
We are talking flash bulb stuff.
Unless you give way more information you better start reviewing you reticence about capacitors and DC.
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: AC Coil Operation
Another option may be the front end out of a switching power supply.
respectfully
RE: AC Coil Operation
Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: AC Coil Operation
Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: AC Coil Operation
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Eng-tips forums: The best place on the web for engineering discussions.
RE: AC Coil Operation
I used a normal thyristor since the actuating pulse was never more than half a cycle. Actually somewhat shorter. The coil was something like 60 mm long and 30 mm wide. Do not remember exact peak current. Must have been one or two amps at 220 V (yes, 220 V - it was before we changed to 230 V).
Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: AC Coil Operation
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Eng-tips forums: The best place on the web for engineering discussions.
RE: AC Coil Operation
thanks
RE: AC Coil Operation
Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: AC Coil Operation
We use to use a bridge rectifier with this coil and it would work fine as low as 16VAC . Now, with the spec changed to 13VAC-190VAC as a range, I not sure it will work at the low end without the rectifier. How do I calculate what kind of coil I need? or perhaps maybe a 2 coil arrangement?
RE: AC Coil Operation
If the coil has a DC rating or if you can change to a DC coil, this problem might be easier to deal with. What prevents using DC?
RE: AC Coil Operation
What is this crap about not being allowed to use certain components while others seem to be OK?
If you were allowed to use a switcher, no sweat!
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: AC Coil Operation
RE: AC Coil Operation