elec. motor

http://142.165.246.187/wiring.jpg
Can someone give me a hand with wiring a 1/4HP electric fan motor? I would
have thought it to have 3 wires - 2 hot and a ground - but theres 4. I want
to be able to reverse the motor with a switch, so I guess I have 2
questions...
1) What do L1, L2, T5, and T8 mean?
2) How do I wire the reverse button? Im more familiar with DC circuits and
never work with AC beyond installing lights and outlets.
Thanks!
Reply to
jacko
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Ok, I figured it out, L1 and L2 are hot, T5 and T8 are for the starter winding, and they go to inside the motor (I didnt realize this).
Double pole double throw switch? What amperage does it need to be rated at for 110V? The wire is AWG18. I have no idea where to buy this.
Reply to
jacko
If you're talking a single-phase AC induction motor, you usually reverse them by reversing the start winding connections. Once they're stopped, reverse the start winding connections and start it again. This usually means you have to bring the start winding connections out of the casing to an external switch.
A 'four-way' household light-switch might work. With 18 gauge wire, it doesn't sound like too high a current draw. But some code experts might know better, so check back to see if there is any code problems with this idea.
daestrom
Reply to
daestrom
Usually T5 and T8 are for forward and reverse. You should be able to use a SPDT switch, properly rated. and put L2 in the middle with T5 and T8 on the outside. This will not turn the motor off, just reverse it.....good luck on your project...Ross
Reply to
Ross Mac
Can you show us a schematic of that?
Reply to
ehsjr
L1 goes to the motor and L2 either connects to T5 or T8 using a SPDT switch.....did I miss something??
Reply to
Ross Mac
I read this after I wired it to be used with a DPDT to reverse them on the terminals they're shown to be on the diagram. I dont understand why your way works, although I dont doubt it will, so I'll use my way because I understand it.
Reverse it while its running? Is that a good idea?
Reply to
jacko
I got it to work, but I dont understand why. THe wiring diagram doesnt show a ground, and the word GROUND is stamped near a bolt on the case. I thought the ground from the outlet goes here, but hooked up like that it doesnt work (plug it in, nothing happens). When I move the ground to terminal 2, along with either T5 or T8 (depending on direction), then it works. I dont understand why the starter winding needs to be grounded, and if it does then why doesnt the diagram show it? I cant damage anything by grounding terminal 2 can I?
Anyway, it works, so now all I need to know is what the DPDT switch needs to be rated at and where to get it. I'm going to use the multimeter to figure out how much amperage is going through T5/T8, then I guess get on the phone and try explaining to stores what I want. This should be fun if my last week search for a standard automotive SPDT relay is any indication, 6 stores and not one person knew what I was talking about until I found a guy that brought out a catalog and let me show him. "PLAIN OLD 12V 30 AMP SINGLE POLE DOUBLE THROW AUTOMOTIVE 5 BLADE RELAY - this is 'auto electric' right?"
Reply to
jacko
I wouldn't reverse it while it is running!!
Reply to
Ross Mac
If the question is "how" to shut it off....the switch should have a center off position..... That would be nuetral to the motor, hot to the switch and T5, T8 to the outside of the switch...
Reply to
Ross Mac
Yes. He's got a total of 6 wires, the hot and neutral supply wires, and 4 wires from the motor. As you see it, where does he connect each wire?
With a SPDT switch, when T5 is switched to L2, T8 is connected to nothing, and vice-versa.
With a DPDT switch, the circuit could be this: hot--L1-motorwinding-L2-T5-startwinding-T8-neutral or this: hot--L1-motorwinding-L2-T8-startwinding-T5-neutral You can't do the above with a SPDT switch. Here's the diagram with a DPDT switch: +---------------------+ | | 0 0---+T5-winding-T8--+ / | | hot--L1-winding-L2--0 | | | | +-----+ | | | 0 0-------------------+ / neutral-------------0
Reply to
ehsjr
Why would you want to switch the nuetral???? Wouldn't that be outside of the switch arrangement????
Reply to
Ross Mac
But now you're putting the motorwinding and startwinding in series. The 'motorwinding' won't see line voltage. The OP said the wires were labeled L1, L2 and T5 and T8. When the startwinding's centrifugal switch cuts out, the whole thing stops (then restarts, then stops, then restarts, until it burns out).
Wouldn't you want.... hot--L1-motorwinding-L2-neutral hot--T5-startwinding-T8-neutral
and for the other direction... hot--L1-motorwinding-L2-neutral hot--T8-startwinding-T5-neutral
I *assume* the start winding has a centrifugal switch connected internally to cut out once the motor is running.
To reverse, a DPDT to reverse the connections to T8 & T5
daestrom
Reply to
daestrom
Right. That's how my fan motor is wired.
Right.
Right - but only if the motor has a centrifugal switch.
Right. We have no disagreement, just two different types of motor.
Reply to
ehsjr
Poor labeling on my part. You wouldn't switch the neutral - you'd switch the hot. Swap the words hot and neutral in the diagram. But it is not relevant to circuit operation - it works the same, regardless of which supply wire is hot and which is neutral.
I don't know what that question means.
I still want to see what you have in mind. Can you draw the circuit you have in mind, that works with a SPDT switch, and switches L2 to either T5 or to T8 ?
Reply to
ehsjr
My assumption was that T5 was forward and T8 was reverse....Then I re-read the OP and realized...there is no nuetral....it must be a 240 or 480 volt motor....L1 and L2 are both hot....I suppose the information in the OP is a bit sketchy....It would be nice to know the model number and make of the motor...Then this could easily be resolved.... And hey, I missed it too!
Reply to
Ross Mac

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