Wiring a new TS motor

[Christopher Fletcher]

So here I go jumping in head first with my recent TS purchase. I ended up getting a new import motor and machined pulleys. As it so happens, the new motor did not include a wiring diagram or other instructions. Hoping maybe someone could point me in the right direction.

The new motor has quite a few wires and the TS has only a pos, neg, and gnd. I assume the INS on the motor case means that I am supposed to cap off the bare ends of these wires. I'm unclear as to the Line 1 and Line 2 descriptors. Also should I solder the joints and insulate, or use a temporary joint for easy removal for servicing. Also, I need to run it on 110.

I am trying get this done over the weekend, but if worse comes to worse I'll wait until monday and contact the vendor for wiring info. Any help is certainly appreciated though!:)

[Tom Veatch]

...
The new motor has quite a few wires and the TS has only a pos, neg, and gnd. I assume the INS on the motor case means that I am supposed to cap off the bare ends of these wires. I'm unclear as to the Line 1 and Line 2 descriptors. Also should I solder the joints and insulate, or use a temporary joint for easy removal for servicing. Also, I need to run it on 110....

Line 1 and Line 2 refers to the black and white input wires coming from the on/off switch. The green wire is the ground wire and will not be used in the motor connection.

To wire the motor for Low Voltage operation, connect the "yel/blk(p1)" wire to either the black or white input wires. Connect the three wires "black(t5)", "white(t2)", and yellow(t4)" to the other input wire.

Connect the other motor wires together in the groups shown in the diagram. Connect "blue(t1)" and "grey(t6)" together in one group, and "red(t8)", "brown(p2)", and "orange(t3)" together in a separate group not connected to the first group or to either input wire. Note: If I've made a typo in this description, go by the diagram on the motor and ignore my description.

I would use wirenuts to make the connections rather than solder or other permanent means. If you do solder the connections together, you need to insulate the connections with something like electrical tape or heat-shrink tubing.

The motor shows a 14.2 FLA at the low voltage so it should be supplied from at least a 20 amp circuit.

[Christopher Fletcher]

Thanks Tom,
This is a great help. A couple questions though, alternating the black and white wire configurations would result in a reverse running motor, correct? As this is a CW running motor (and cooling fan) is there anything that can tell you which wire should be line 1. Or just T & E?

All the jacks in the garage are 20A, so I should be square.

[Brandon Shew]

The green wire is the ground wire and will not be used in the motor connection.

I would definitely suggest connecting the ground wire on a 115V application.

[Christopher Fletcher]

I would definately suggest connecting the ground wire on a 115V application.

FWIW, The ground wire was not connected on the original motor. It just lay loosely within the circuit box. Also, I see no gnd wire coming from the motor. Would I just drill, tap, and wrap around a bolt on the case?

[Mike Henderson]

Thanks Tom,
This is a great help. A couple questions though, alternating the black and white wire configurations would result in a reverse running motor, correct? As this is a CW running motor (and cooling fan) is there anything that can tell you which wire should be line 1. Or just T & E?

All the jacks in the garage are 20A, so I should be square.
Reversing the black and white (input) wires will not reverse the motor. To reverse the motor you should interchange the internal red and black wires as shown on the data plate.

Mike

[Mike Henderson]

I would definitely suggest connecting the ground wire on a 115V application.
I agree. You should always ground your equipment.

Mike

[Dan Friedrichs]

As an electrical engineer, I just wanted to confirm that the previous posters have been correct in their instructions as to the wiring.

Also I agree that your should just tie the wires together with wire nuts (not solder).

To ground it, tie the green wire to the metal junction box somehow. A bolt or self-tapping screw would work fine. Obviously, the junction box ought to be electrically connected to the rest of the metal parts of the saw.

Dan

[Bill Huber]

Christopher, please don't take offence at this but I really think you should have a contractor come in and do it.

Why I make this statement is when you said neg. and pos. when talking about AC and the fact that the motor did not come with a wiring diagram when there is a good one on the motor.

I would just hate to see you hurt yourself or burn up your motor.

[Dan Friedrichs]

Bill - it's always a good idea to be safe about this, but I think the OP can handle it. I agree that the wiring diagram is a little confusing. As long as he isn't touching any live wires, the danger is nearly non-existant, and the risk of damaging the motor so small (and the value of the motor so low), that it wouldn't be worth the cost of an electrician.

For reference, it's not entirely incorrect to say that AC has a positive and negative. For a standard 1-phase AC line, the "hot" is often called positive (keeping the convention with DC systems). The neutral is then, of course, negative. For 240V AC, there is not a positive and negative, though - both lines have 120VAC (with respect to neutral/ground), just 180 degrees out of phase.

[Wade Lippman]

Christopher, please don't take offence at this but I really think you should have a contractor come in and do it.

Why I make this statement is when you said neg. and pos. when talking about AC and the fact that the motor did not come with a wiring diagram when there is a good one on the motor.

I would just hate to see you hurt yourself or burn up your motor.

When people ask what to do with all the wires when they install a subpanel, I cringe. They would have to be crazy to do it themselves.

But it is pretty darn simple. Connect the wires as described. Hard to do it wrong, and the worst that can happen is that it burns up.
I am pretty good with electrical now, but years ago when I knew nothing I wired up a motor almost exactly like this; easy as cake.

[Mike Henderson]

For reference, it's not entirely incorrect to say that AC has a positive and negative. For a standard 1-phase AC line, the "hot" is often called positive (keeping the convention with DC systems). The neutral is then, of course, negative. For 240V AC, there is not a positive and negative, though - both lines have 120VAC (with respect to neutral/ground), just 180 degrees out of phase.
That's absolutely incorrect. On any AC circuit, there is no positive or negative except as alternating positive and negative. The fact that one line is connected to ground in the 120V circuit does not make it "negative", even if some people call it that.

Assigning the terms "negative" and "positive" to an AC circuit does nothing to clarify the operation of the circuit.

The more common terms used for a 120V circuit is "hot" for black and "neutral" for white. At least among all my electrical friends.

Mike

[I'm an electrical engineer also and have friends in the power business. I've never heard any of them refer to one side of an AC line as "positive" or "negative" except as a transient state - even the old timers who came up with DC motors (but now design AC systems).]

[Christopher Fletcher]

Bill,
I certainly do not take offense to your suggestion, but I am more of a do-it-yourself kind of guy. If I hired someone for everything I was unfamiliar with: 1. I'd would have a rather thin wallet. 2. I would never learn what could often be basic skills. Nonetheless, I do not take safety lightly and value your concern.

Mike, thanks for the clarification concerning the spin direction. I read that instruction on the case several times, and somehow got a bit wrapped around the axle thinking about Line 1 vs. Line 2.

My relative wiring experience has come from car audio installs and such. I was not familiar (obviously) with the wiring instructions given on the case. The biggest ? was with regard to line 1 and line 2. Now that the mystery is solved, I think I can tackle this project.

Thanks to everyone who replied with their input.

[Christopher Fletcher]

FWIW, I have several times incorrectly referred to hot vs neutral as positive vs negative and also been several times corrected. I suppose one of these days it will stick....

Now if you want to know about mechanical turbulence and gravity waves as it pertains to the vertical motions of wind and atmospheric stability, then I'm your man.:)

Thanks again!

[Tom Veatch]

Thanks Tom,
This is a great help. A couple questions though, alternating the black and white wire configurations would result in a reverse running motor, correct? As this is a CW running motor (and cooling fan) is there anything that can tell you which wire should be line 1. Or just T & E?

All the jacks in the garage are 20A, so I should be square.

Reversing the L1 and L2 lines will not cause the motor to reverse direction. You're working with alternating current, so there are no positive and negative leads. L1 and L2 reverse polarity 60 times per second so, in effect, from the standpoint of polarity, L1 and L2 reverse themselves continuously. Therefore, it doesn't matter which one you call L1 and which one you call L2, IN THIS PARTICULAR CASE.

In circuit wiring of 120v circuits, it definitely makes a difference, but inside the motor, the motor itself can't tell the difference.

I said that the green wire isn't used in the motor connections. That is correct. The green wire is the Equipment Grounding Conductor and does not carry current to power the motor. It will not be connected to any of the wires shown in the motor's wiring diagram. It should however be connected to the motor case and saw chassis to ground those items and provide a path for current to flow to ground should a fault develop inside the motor.

[Christopher Fletcher]

Well the motor is wired and running with the correct orientation, so again thanks to all. The new motor is very quite. Such a night and day difference that I won't be looking back. I have a new machined upper pulley and link belt coming my way sometime early next week. I should be working on dust collection for it by the end of the week!

[Bill ThompsonNM]

I've been doing my own wiring since I was about 12, but I do want to make sure it's always done properly and to code. To that end, I use and recommend two books:
"Wiring Simplified" by Richter et al, Park Publishing. It used to come with a hole in the top to hang it on a nail on a stud, but not anymore. It does cover most of what anyone should need to know for wiring a workshop (including sections on motors) If you need more depth: "Practical Electrical Wiring" by the same authors and publisher. Both are revised with each new version of the National Electrical Code. If you need more information than these volumes, you probably need to either call a very qualified electrician or order a copy of the NEC yourself.
:)

[Dan Friedrichs]

Mike - I agree that it's very bad nomenclature, I was just pointing out that saying positive and negative with respect to AC systems is not uncommon (although it is technically "wrong"). A lot of people seem confused about the voltage on the neutral line - there seems to be a good number of people who think the neutral carries an AC wave as well (which is not true unless it's a 240V circuit, in which case it's not called the "neutral"). Calling the "neutral" "negative" seems to be a way that some people use to reason that the neutral is closer to ground.

[Mike Henderson]

Mike - I agree that it's very bad nomenclature, I was just pointing out that saying positive and negative with respect to AC systems is not uncommon (although it is technically "wrong"). A lot of people seem confused about the voltage on the neutral line - there seems to be a good number of people who think the neutral carries an AC wave as well (which is not true unless it's a 240V circuit, in which case it's not called the "neutral"). Calling the "neutral" "negative" seems to be a way that some people use to reason that the neutral is closer to ground.
Dan - I understand your point but there's nothing about ground that would make it more "negative" than "positive".

+++++++
Warning - long discussion of residential power distribution!:)
+++++++

Single phase residential power is supplied by a transformer which has a center tapped secondary. The voltage across the full secondary is 240V and the voltage between the center tap and either of the "outside" wires is 120V.

When a load is supplied with either 120V or 240V, there is an alternating (at 60Hz in the US) voltage across the two supply leads.

In the US, the center tap is tied to ground for safety reasons. But just for our discussion right now, let's pretend that the center tap is not tied to ground and that all of the supply lines are floating referenced to ground.

The voltage between any two supply wires will be either 120V or 240V alternating at 60Hz. The difference is that if you touched any one of the supply lines (but not both at the same time) you would not receive a shock because there would be no return to the secondary of the transformer.

In the US, we tie the center tapped wire to ground. The voltage between any two supply lines is either 120V or 240V, but if you touch one of the "hot" wires (the wires connected to the outside of the secondary wiring) you will receive a shock because now there's a return in the circuit.

Looking at the first case (ungrounded), if you were to measure the voltage between any wire and ground, no voltage would be indicated because the circuit is not completed.

In the second case (grounded), if you measure the voltage between ground and neutral, you will not measure any voltage because neutral is tied to ground. If you measure from either of the "hot" wires to ground you will obtain a reading of 120V. If you measure across any two wires you will obtain a reading of 120V or 240V, depending upon which wires you measure across.

So my point - the neutral does indeed carry an AC wave, but it carries it relative to the hot wires in the system. Since the neutral is tied to ground, there is no voltage between it and ground.

-----

And now, a side discussion. If you won't get shocked in an ungrounded system unless you touch the two supply wires at the same time, why do we ground the system in the US, which allows someone to get shocked by touching one supply wire?

The reason, surprisingly, is safety.

The problem with an ungrounded system is that you can have an inadvertent ground. For example, suppose you had a grounded metal outlet box and one of the supply wires came in permanent contact with the box. Nothing would happen because there's no return in the system. But now, you've made the system dangerous. If one of the outside wires were grounded, the voltage from the center tap to ground is 120V and the voltage from the other outside wire to ground is 240V. If someone contacts that other "outside" supply wire, they will receive a shock of 240V (to ground) - much more lethal than 120V.

The philosophy behind the design is that "the devil you know is better than the devil you don't know". If you have a ground designed in, you now have to provide certain kinds of protection but the system is known and consistent. When you have an ungrounded system, you can have a ground and not know it.

Additionally, by tying the center tap to ground, the maximum voltage to ground is 120V. The only way you can receive a 240V shock is to simultaneously touch both supply wires of a 240V circuit.

Anyway, long discussion to show that the neutral does indeed carry an AC wave, but only in reference to the other supply wires.

Mike

[Re-reading this post, it appears that I'm one of those engineers who tell you how to build a clock when you ask me "What time is it?" Sorry, it's an occupational hazard.:)]

[Tom Veatch]

...[Re-reading this post, it appears that I'm one of those engineers who tell you how to build a clock when you ask me "What time is it?" Sorry, it's an occupational hazard.:)]

I can empathize with you on that, Mike, having written a few "clock-building instructions" myself. But, I must say, you do it pretty well.

[jerry nazard]

Mike and Tom:

You both seem to consistently provide accurate and timely information....

[John Ricci]

There is some really great info in this pdf that simplifies wiring single/multiphase induction motors but it helps if you are comfortable/competent with electrical supply wiring to begin with...a good reference, this.

http://www.electrofed.com/_files/file.php?fileid=filepsDdfiXRBm&filename=file_M2_1_EEMAC_Standard_For_Lead_Marking ___Connections_For_Single_Phase___Polyphase_Induct ion_Motors.pdf

J.R.