Compact time delay on open relay needed
Compact time delay on open relay needed
(OP)
I am looking for a small (~1"^3) solid state relay that will start a 120V 1/4hp AC blower when the power comes on. After 10 or 15 minutes it will open the circuit.
The application is a confined space with a blower. The blower is currently equipped with a timer set to run the blower twice a day for 15 minutes (every 12 hours).
However, if the power is interrupted to the vault, it could be more than twelve hours between blower cycles. I would like the blower to run immediately after the power comes on after an interruption (without regard as to how long the power is off).
The application is a confined space with a blower. The blower is currently equipped with a timer set to run the blower twice a day for 15 minutes (every 12 hours).
However, if the power is interrupted to the vault, it could be more than twelve hours between blower cycles. I would like the blower to run immediately after the power comes on after an interruption (without regard as to how long the power is off).





RE: Compact time delay on open relay needed
Just make sure the proper safety requirements are satisfied.
RE: Compact time delay on open relay needed
http://www.natcon.com/timer1-8.htm
8A relay contact should handle 1/4HP 120V motor (5.8A) but check with them first.
Quando Omni Flunkus Moritati
RE: Compact time delay on open relay needed
RE: Compact time delay on open relay needed
Thanks for the responses.
DanDel
Due to the high humidity environment, I am looking for a solid state relay.
Most plug-in relays are larger than the 1-cubic inch space requirement.
jbartos
The relay that is inked in your message will turn on after the delay. Thus, it will require a second relay to control the fan. It too is larger than 1"^3.
Any other recommendations?
RE: Compact time delay on open relay needed
RE: Compact time delay on open relay needed
The only suggestion I can make is to contact a firm specializing in custon-design microminiature solid-state circuits. There are others that use open, but potted circuitry.
However, unless you are talking about large quantities it will be extrordinarily expensive. If you need an example of development costs, let me know!
RE: Compact time delay on open relay needed
Who makes the potted relays? I would like to know more ablut them.
RE: Compact time delay on open relay needed
The potted "circuit", not relay, company is "Artisan Electronics" in Parsippany, NJ. This is a time-delay relay company, so you probably won't need a schematic.
The custom design house is "Aptek" in Deerfield Beach, FL. This company, at least in the past, required a schematic.
RE: Compact time delay on open relay needed
http://www.amperite.com/st2.htm
Do what I want? I might be able to make it fit.
RE: Compact time delay on open relay needed
The second problem is interfacing the "solid-state" module with existing circuitry. I say that because Amperite uses a triac to drive the load. Thus, to interface the two, then the Amperite unit will have to drive a relay, that in turn, is used to control the motor. Ergo, more hardware.
RE: Compact time delay on open relay needed
The second problem is interfacing the "solid-state" module with existing circuitry. I say that because Amperite uses a triac to drive the load. Thus, to interface the two, then the Amperite unit will have to drive a relay, that in turn, is used to control the motor. Ergo, more hardware.
Are you saying that the triac will not be able to run the 1/4HP blower or that it will damage the blower? (I have never tried to use a solid state relay.) Will the leakage current cause the blower motor to heat? Why is the relay necessary?
RE: Compact time delay on open relay needed
Coincidently, at one time my company supplied a device such as the one you are seeking. It was called a "Motor Reacceleration Module!" It was used to reaccelerate large numbers of motors, particularly for the HPI industry, following a momentary loss of power! Unfortunately, it is no longer available. And, if it were it would have been much too large for your intent, even allowing for your concession on size.
If you are still interested contact me off-line, and I can provide you with some ideas, but, remember, it will never meet your size criterion.
RE: Compact time delay on open relay needed
jbartos
The relay that is inked in your message will turn on after the delay. Thus, it will require a second relay to control the fan. It too is larger than 1"^3.
///I do not have any relay linked in my message since there is no link. Essentially, my posting expressed a concern about the physical size of the linked relay in jraef posting.\\\
RE: Compact time delay on open relay needed
RE: Compact time delay on open relay needed