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I have a mark 5 . When useing the table saw at correct speed the motor blows my breaker. This only happens at ther saw RPMs . If I turm RPMs up it is ok or if I turn the RPMs down a tad it runs ok. This motor even blows the breaker when splitting a piece of pine. I cleanded and lub everything even the shethes. Can anyone tell me what they think.
thanks

jaden wrote:I have a mark 5 . When useing the table saw at correct speed the motor blows my breaker. This only happens at ther saw RPMs . If I turm RPMs up it is ok or if I turn the RPMs down a tad it runs ok. This motor even blows the breaker when splitting a piece of pine. I cleanded and lub everything even the shethes. Can anyone tell me what they think.
thanks

There has been a lot of discussion about this situation. You are definitely not alone. Unless you have already done some rewiring, I would guess that you are running on a standard household circuit which is 110vac, 15amp, using 14gauge wire from the outlet to the main breaker panel. You also have the Shopsmith power cord and possibly an extension cord (I hope there is no extension cord).

This setup will work most of the time but occasionally does beg the problem you describe. If, for any reason, your line voltage coming to the house is low it will maybe work some of the time.

You also may be sharing this service line (in your shop) with other outlets. The Shopsmith at startup draws at least 13 amps; almost enough to kick the breaker. If the voltage is low or you have other items drawing on this same circuit, a popped breaker is almost absolute.

Bottom line: 1) Make sure the Shopsmith is running on a separate circuit. 2) Eliminate any extension cords. 3) Check line voltage to make sure it is at least 110 vac.

After making sure that you comply with these three suggestions and you still have the same problem - I would suggest that you need a 20 amp breaker wired to your shop area with 12 gauge wire and that you still operate the Shopsmith on a dedicated circuit.

One other question. When you turn on your Mark V, does it seems to come to speed rapidly or does it takes some time. I know this is very subjective but it is an important indicator.

If it comes up but comes up slowly, this tends to mean inadequate power at the motor and some other testing is necessary.

Are you technically prepared to do this task on your own and do you have a volt/ohmmeter?

Incidently, welcome to the forum.

Dusty, thanks for your quick reply. My answers to your questions are as follows. The saw is on with my lights aswell,(2 8ft floressents). I have run other table saws on this circut before with no problem. Also as I stated ,it only blows the breaker if I am at the saw RPMs. I can cut with lesser RPMs with no problem but this is not correct and I should not have to. Yes it is on a 15amp breaker and changing it to a 20 is a fine suggestion and I will. Also the motor slows down at saw speed before the breaker goes even if I am riping a piece of pine. It (motor) just seems to slow down at saw speed only.
Jaden

jaden wrote:Dusty, thanks for your quick reply. My answers to your questions are as follows. The saw is on with my lights aswell,(2 8ft floressents). I have run other table saws on this circut before with no problem. Also as I stated ,it only blows the breaker if I am at the saw RPMs. I can cut with lesser RPMs with no problem but this is not correct and I should not have to. Yes it is on a 15amp breaker and changing it to a 20 is a fine suggestion and I will. Also the motor slows down at saw speed before the breaker goes even if I am riping a piece of pine. It (motor) just seems to slow down at saw speed only.
Jaden

Don't install a 20amp breaker unless you have 12 gauge wire from the breaker to the outlet. Doing so could be a fire hazard. The 14 gauge wire is not heavy enough to carry a continuous the 20amp load.

dusty wrote:Don't install a 20amp breaker unless you have 12 gauge wire from the breaker to the outlet. Doing so could be a fire hazard. The 14 gauge wire is not heavy enough to carry a continuous the 30amp load.

Didja mean 20?????

The 1 1/8 HP ss motor draws 13.5A at rated load. The two 8' lights would probably exceed the 1.5A 'headroom'. The ss motor draws way more at startup. I understand how slowing down 'helps' but speeding up is confusing unless the saw has enough inertia to 'help'. Perhaps a dull teeth portion on the blade is causing load to leap frog so to speak.

The current draw is the reason ss limited the motor to 1 1/8 HP(it will run on a 15 amp circuit with no other 'loads'). Unfortunately few houses have a 'dedicated' branch circuit.

I have rambled a bit here, but hope it is helpful to your understanding.

Welcome aboard!

Another (remote) possibility is the breaker is tripping prematurely. If it is located near other breakers that are helping heat it that could cause over sensitivity as well as a poor connection(creating heat) at either the wire or buss.

Do not merely replace with a 20A breaker unless the circuit is wired with #12 ga wire.

Also make absolutely sure there is nothing else on that circuit!!!!!

JPG40504 wrote:Didja mean 20?????

Yes. That is what I said but not what I typed.

dusty wrote:Yes. That is what I said but not what I typed.

If only our fingers knew what our mouth was saying!:D

jaden wrote:I have a mark 5 . When useing the table saw at correct speed the motor blows my breaker. This only happens at ther saw RPMs . If I turm RPMs up it is ok or if I turn the RPMs down a tad it runs ok. This motor even blows the breaker when splitting a piece of pine. I cleanded and lub everything even the shethes. Can anyone tell me what they think.
thanks

I hope that you have gotten your problem resolved and that you are now happily making sawdust, jaden. But, in case you have not, I am going to post something that I compiled some time back as a direct result of someone elses similar problem.

Your situation, as you describe it, is somewhat atypical in that you say the problem only occurs if you startup at saw speed. Startup speeds both above and below saw speed work without difficulty. I have no explanation.

Some users turn the speed down before they turn the machine off. By doing so, startup is always at low speed. I believe that is unnecessary but some disagree.

Following is the information that I collected. Remember, this is only a single data collection point and involves only one machine in one shop.

Crafters Station

The Crafter&#8217]Mark V[/B]

I collected data on the Mark V in two different configurations. I did one test with the Mark V plugged into a 15’ extension cord (14ga) and the other without the extension cord.

With the extension cord, the momentary (about 2 sec) startup demand current is just a bit below 30 amperes. Once the Mark V reaches run speed, the current draw settles at 8.0 amperes. Starting up at low speed is slightly different than starting up at high speed. There is a slight difference in the duration of time when the machine draws that extra “startup current”. With the machine set at saw speed, the peak draw lasts for about 3 seconds.

Without the extension cord, the momentary (about 3 sec) startup demand current current is still 30 amperes. Once the Mark V reaches run speed, the current settles in at 7.5 amperes. The extension cord accounts for approximately 1/2 ampere of the total current drawn by the Mark V in this configuration. It is my opinion that the use of an extension cord (of reasonable length) should not be a problem.

While ripping ½” and ¾” stock, the current draw increases to between 8.5 and 9.0 amperes.

While “attempting” to rip a piece of 2” alder, the Mark V was laboring. I had to back off to keep from stalling the motor. I saw current draws as high as 20 amperes. I did achieve a clean cut but had some burning (on the piece against the fence). The cutoff was not discolored and the cut is clean. I was using a heavily used blade but one that is still reasonably sharp.

If I had not backed off when the Mark V labored, I could easily have tripped the 15 amp breaker that I was operating on. I normally operate on a circuit that has a 20amp breaker.

I believe that if I did not have time-delay breakers, the startup currents could be high enough and long enough in duration to trip the breakers.

Guys, I put the SS on a seperate circut and it seems to be ok
Thanks
yes dust is flying