Mamac Current Sensing Switch/Switches, CT-800/CT800 NEW on Ebay

[BraveSirRobbin]

Steve;

If this is truly a "current" sensor it should have the same trip point sensitivity no matter what the voltage is. The problem may be though that 220 volt devices will draw less current for a given 120 volt device for a similar application.

You can calculate this as Power = Voltage * Current (or Watts = Volts * Amps)

 

[jwilson56]

Steve;

If this is truly a "current" sensor it should have the same trip point sensitivity no matter what the voltage is. The problem may be though that 220 volt devices will draw less current for a given 120 volt device for a similar application.

You can calculate this as Power = Voltage * Current (or Watts = Volts * Amps)

That maybe the case but one leg of the 220 will be running the motor as most likely is runs on 110V

 

[mustangcoupe]

My thoughts exactly John as I was reading his posts and thinking that motor is pulling more then 1 amp when on... I am sure of it! I bet they use one leg for the motor and use the 220 for the heaters

 

[electron]

I am pretty sure they only use 1 leg for the motor, but it has been a while since I had to replace my dryer motor.

 

[SteveQ]

I am pretty sure they only use 1 leg for the motor, but it has been a while since I had to replace my dryer motor.

So, if I put the current sensor on the opposite leg of the 220V, it might stay ON as long as the dryer is running? Interesting, I will have to try that. I just assumed a 220V motor was used.

Steve Q

 

[jwilson56]

I am pretty sure they only use 1 leg for the motor, but it has been a while since I had to replace my dryer motor.

So, if I put the current sensor on the opposite leg of the 220V, it might stay ON as long as the dryer is running? Interesting, I will have to try that. I just assumed a 220V motor was used.

Steve Q

Very doubtful that the motor is 220. You will have to test one side then the other

 

[felixrosbergen]

Don't most modern electric dryers come without a cord and just some termination lugs in a small panel on the back of the dryer? Mine surely did. Because of different 220v outlets in different age homes they just provide the terminals and when you order you have to tell them what outlet you have and they throw in the correct plug/cable.

It shoudl be pretty easy to take the cable of the lugs, pass is through the CT and put it back on. With a clamp on Amp meter you coudl first test which leg you need.

 

[beelzerob]

Is there some reason you wouldn't pass both legs through? I was watching the Brultech data last night as the dryer was running and the amps kept jumping and then dropping, as the heater came on and off. Why not just put both legs through? Could the dryer really pull an amp without actually running?

 

[upstatemike]

Is there some reason you wouldn't pass both legs through? I was watching the Brultech data last night as the dryer was running and the amps kept jumping and then dropping, as the heater came on and off. Why not just put both legs through? Could the dryer really pull an amp without actually running?

If you put both legs through the 220V current (heater) should cancel and not be detected but the 120V (motor) that returns to neutral should be detected. Putting the detector on the neutral wire in the dryer pigtail should do the same thing.

 

[beelzerob]

I probably don't understand 220 (other than it's an owie). I thought there were 2 hot legs, 1 ground, and 1 neutral. Or by cancelling out, do you mean the phase difference between the 2 hot legs? I thought the cancelling only occured if the current was flowing in different directions.

 

[upstatemike]

I probably don't understand 220 (other than it's an owie). I thought there were 2 hot legs, 1 ground, and 1 neutral. Or by cancelling out, do you mean the phase difference between the 2 hot legs? I thought the cancelling only occured if the current was flowing in different directions.

If you put both legs of 220V circuit through the detector then current for 220V loads would be flowing in different directions (up one leg and back down the other) so the current would cancel. The 120V load would go up one of the legs and return on the neutral so it would be detected. Putting the detector on the neutral of the dryer pigtail would also detect the 120V return current but not the 220V current which is only present on the two hot leads.

 

[mustangcoupe]

I probably don't understand 220 (other than it's an owie). I thought there were 2 hot legs, 1 ground, and 1 neutral. Or by cancelling out, do you mean the phase difference between the 2 hot legs? I thought the cancelling only occured if the current was flowing in different directions.

I have an older style plug with 2 hots and a third wire... I guess this third wire is the neutral/ground.........

 

[jwilson56]

BTW I was looking for some cheap short Appliance Extension Cords to use with these current sensors and came across these. They look like it will be easy to separate one lead out to wrap around. This is makes for an easy install without cutting into the original cord on whatever your trying to monitor.

Shipping was not too bad either.


http://www.4compuelectron.com/apps/details...64346&enc=1

 

[mustangcoupe]

keep your eyes open on ebay I just picked up 3 GREYSTONE CURRENT SWITCH P/N CS-GNG-L 10-07A L-14 which look to be the same as the ones in the original post of this thread, 1 amp switch current.... total 19.99 shipped

 

[Lagerhead]

GREYSTONE CURRENT SWITCH P/N CS-GNG-L 10-07A L-14 which look to be the same as the ones in the original post of this thread, 1 amp switch current

Thanks for this lead, I found the Mamac sensors to be way more useful than I thought and I could use a couple more.

Note this small point, which may be important in some applications --
- The Mamac sensors have an environmental rating of -50°C to +65°C (-58°F to 149°F) [which is nice as I have one sensing my attic ventilation]
- The Greystone sensors seem to be for "indoor" use, 0°F to 40°C (32°F to 104°F)