With the wiring you describe, and 230 volt system. I'd call the black wire hot, and I'd call the yellow wire hot.
Christopher A. Young Learn more about Jesus
From looking at my diagram, the motors only appears to be only 230v at start up. Excludingthe capacitor, that leaves two wires: Black and Yellow. Black is "Hot". Just what, then, are you going to call the other wire--do you prefer the term "neutral"?
Bill
Please correct me if I'm wrong, but I am thinking it is only a 230v system because of the capacitor. There appears to be only 1 pole powering the fan motor. Does one refer to both wires power a 110v appliance as hot? Admittedly, they are both carrying current.
In your terms, the latter hot wire is connect to common, or somewhat equivalently, back at the main panel, ground.
Bill
Please correct me if I'm wrong, but I am thinking it is only a 230v system because of the capacitor.
CY: Most central AC and heat pumps, use 230 volt compressor, and 230 volt fans.
There appears to be only 1 pole powering the fan motor.
CY: One pole is switched.
Does one refer to both wires power a 110v appliance as hot? Admittedly, they are both carrying current.
CY: In 110 appliances, there is typically a black hot, and a white neutral.
In your terms, the latter hot wire is connect to common, or somewhat equivalently, back at the main panel, ground.
CY: From the fan wiring I've done, black and yellow are both hot.
But only when the fan is actually running, right (see what I mean, there IS a difference). Kind of like whether you put a disconnect in front of an appliance or after it.
TY VM SM! I've "seen you around" the Usenet
Bill
Both black and yellow are hots. One of course is switched. So, one is hot only when the contactor is pulled. (switched hot, y'know.) But, if you follow the wires to the other side of the contactor, they are both hot, all the time.
In the case of 110 volt appliance, one is hot, other is neutral. Switched on or off.
YW, glad to have met you around the usenet.
Christopher A. Young Learn more about Jesus
But only when the fan is actually running, right (see what I mean, there IS a difference). Kind of like whether you put a disconnect in front of an appliance or after it.
TY VM SM! I've "seen you around" the Usenet
Bill
As I had my condensing unit disconnected for a few days, I reconnected it to evaporate any of the refrigerant that may possibly have combined with the crankcase oil. Even if I replace the fan, I'll be sure 24 hours have passed before I test the system. That's the "standard" waiting period, isn't it?
Bill
You could always heat the crankcase with a propane torch. ^_^
TDD
I think there's a waiting period, and a background check. Oh, you were talking about crankcase heaters?
Christopher A. Young Learn more about Jesus
As I had my condensing unit disconnected for a few days, I reconnected it to evaporate any of the refrigerant that may possibly have combined with the crankcase oil. Even if I replace the fan, I'll be sure 24 hours have passed before I test the system. That's the "standard" waiting period, isn't it?
Bill
What? And avoid the background check?
Christopher A. Young Learn more about Jesus
You could always heat the crankcase with a propane torch. ^_^
TDD
That shouldn't be a problem or an issue unless its either a heat pump and its winter, or you turned the condenser upside down.
It depend on type gas was in system and type of oil??? You as technician must decide that at time you examine the equipment.
The length of the line is an important fact took no?
Yes, it's a heat pump. The "Assembly Booklet" says to wait at least 24 hours, so I will.
Thank you, Bill
Oh, I didn't notice you said "and its winter".
SM: I think I'm getting it at another level. There nothing to keep what's on Common from coming back, if you will, and zapping you in the butt!!! : ) I'd say that qualifies it as "hot". Is that about right?
Bill
I believe SM is incorrect. NEC requires both legs (conductors) to be disconnected by the contactor for a 240VAC load.
The motor will be a single phase 240VAC 60HZ motor (well, technically split phase, but there is a single electrical phase driving it).
Each of the black and yellow will measure 120v to ground if you test them with a multimeter, and they should test 240v to each other when the load side of the contactor is energized (the line side of the contactor will measure hot unless the compressor disconnect is activated or the breaker is disenaged).
scott
Christopher A. Young Learn more about Jesus
SM: I think I'm getting it at another level. There nothing to keep what's on Common from coming back, if you will, and zapping you in the butt!!! : ) I'd say that qualifies it as "hot". Is that about right?
Bill
Hmm. I've worked on a lot of illegal devices, then. Most residential AC outdoor units have a single leg that's switched.
Christopher A. Young Learn more about Jesus
I believe SM is incorrect. NEC requires both legs (conductors) to be disconnected by the contactor for a 240VAC load.
The motor will be a single phase 240VAC 60HZ motor (well, technically split phase, but there is a single electrical phase driving it).
Each of the black and yellow will measure 120v to ground if you test them with a multimeter, and they should test 240v to each other when the load side of the contactor is energized (the line side of the contactor will measure hot unless the compressor disconnect is activated or the breaker is disenaged).
scott
Thank you for helping me to accept that. Alot of evidence was building up on that side, and I've been fighting it tooth and nail. The wiring diagram, and the rest of the pieces, makes more sense in that light!
Dern lady at the electrical supply emphasized I should attach the yellow wire to Common!!!
Thank you again!
Bill
One leg remains energized with miliamp current so that winding acts as a crank case heater in the compressors. this is especially important in heat pumps.
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