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Sparky Boy
May. 17, 2012, 05:00 PM
I searched but couldn't find a thread.

Is it safe to use a plug in timer on barn fans? I use the farmtek sealed motor fans.

NBChoice
May. 17, 2012, 07:35 PM
Hmmm, not sure. We use ones that shut off after 75 degrees and below. Haven't had any trouble with those after many, many years.

Frank B
May. 17, 2012, 07:52 PM
Yes, as long as the fan does not exceed the load capacity of the timer and the timer is designed for inductive (motor) loads.

Most are, and if not, there should be a warning label on the timer.

Sparky Boy
May. 17, 2012, 09:40 PM
Yes, as long as the fan does not exceed the load capacity of the timer and the timer is designed for inductive (motor) loads.

Most are, and if not, there should be a warning label on the timer.

How do I know what the load capacity is?

Frank B
May. 18, 2012, 08:15 AM
Either the fan or the motor itself will have a nameplate listing Amps drawn, and the timer will have one listing the Amps it can carry, typically 10 or 15.

The fan/motor Amps should be less than the timer Amps.

Sparky Boy
May. 18, 2012, 03:32 PM
Either the fan or the motor itself will have a nameplate listing Amps drawn, and the timer will have one listing the Amps it can carry, typically 10 or 15.

The fan/motor Amps should be less than the timer Amps.

Thanks Frank!

clanter
May. 18, 2012, 04:05 PM
Either the fan or the motor itself will have a nameplate listing Amps drawn, and the timer will have one listing the Amps it can carry, typically 10 or 15.

The fan/motor Amps should be less than the timer Amps.

if the fan or electric motor's amp draw exceeds the rating of the timer just use the timer to drive a relay or motor control contactor that is rated to the level of amps required.

These are dumb devices they really do not have a clue as to what they are doing.

Sparky Boy
May. 19, 2012, 11:49 AM
Looked up the amps for my fans. They never go above 2 amps for even high speed, which I refer to as "hurricane speed".

clanter
May. 20, 2012, 09:34 AM
before you switch over to a timer, with all other normally used devises turned on record the primary power voltage at rest then at start up of the fans and then while running.

If you record a voltage drop of greater than a few percentage points you may see premature failure of the timer's relay... normally the failure will be the points in the relay switch will fuse/melt together

ljcfoh
May. 20, 2012, 09:06 PM
before you switch over to a timer, with all other normally used devises turned on record the primary power voltage at rest then at start up of the fans and then while running.

If you record a voltage drop of greater than a few percentage points you may see premature failure of the timer's relay... normally the failure will be the points in the relay switch will fuse/melt together

Clanter,

I am sure you are being super helpful, but I think you need to dumb it down about 50 notches...maybe the OP gets it, but wow you lost me right after switch over to a timer. :)

ThisTooShallPass
May. 20, 2012, 10:00 PM
Check your normal volatage draw. Write down what it says

Turn on everything BUT the fans with their timers. Write down how much voltag is being used.

Then, turn on everything AND the fans with their timers altogether at once, & see much voltage they use when they initially kick on. Write that down & do the math to see if it dropped (minused) more than a few percentage points.

And also while it ALL continues to run write down the voltage being drawn (used). Again, write that down & do the math to see if it dropped (minused) more than a few percentage points.


If you see the voltage dropped more than a few percentage points from your very original reading (normal volatge draw), especially at the moment/point in time EVERYTHING including the fans with timers on was intially turned on, you are creating a danger & could be royally screwed. *danger will robinson danger* Only it is not some fictional tv character at risk, it is your barn!


"Normally the failure will be the points in the relay switch will fuse/melt together " The "relay switch" will probably melt if there was a drop in voltage of more than a few percentage points.



Take her advice seriously. Check. Do the math. Get help checking & doing the math if need be.


Did that explain it? If not, someone else can take a crack at it.

Sparky Boy
May. 21, 2012, 12:40 PM
Nope, went way over my head too ljcfoh!

So I'm thinking I need a voltage meter? I think there is such a thing....

And where exactly does one check the voltage? Somewhere on the panel?