Power consumption

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dusty
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Post by dusty »

wa2crk wrote:Dusty
Your highlighted statement is a fact. One of the reasons why I wanted to investigate. The rest, maybe.
Bill

I assume the band saw is on a power stand.

If so, we are talking two motors drawing simultaneously from the same circuit. Startup together, I would expect a breaker to trip. Run together, I would expect to be OKAY.

Guess I gotta go to the shop.

I have been to the shop.

My dust collector and Power Station running together draw about 13 amps. The dust collector alone draws about 6 amps.

If I start them together, they momentarily draw over 30 amps according to my meter. I am not sure that is correct. The 15 amp breaker did not trip but it seems it should have and certainly would have if that current demand lasted much longer.

I deliberately tripped the breaker to make certain it was not defective but I did that with a direct short. Not conclusive.

Bottom line - my numbers are not much different than yours and with that much start up current, I believe my breaker should have tripped.
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Dusty
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wa2crk
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Post by wa2crk »

Dusty
Machines were not started simultaneously. Dust collector is 9 amps and the bandsaw on the power stand was 6.5 so 15.5 amps for about three minutes and "click". one of the reasons for the tests was to get accurate figures.
Bill
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JPG
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Post by JPG »

IIWM, I would add a 20A circuit.;)
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Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10
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wa2crk
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Post by wa2crk »

JPG
My bad. The main circuit is 20 amp however sometimes I run two items through a power strip which has a 15 amp circuit breaker. The 20 amp ckt was installed by the builder for charging a golf cart(I don't have one) so that circuit is the one for the shop gear. Now I know what I can run together and what not to run at the same time.
Thanks for everyone's input.
Bill V
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dusty
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Post by dusty »

wa2crk wrote:JPG
My bad. The main circuit is 20 amp however sometimes I run two items through a power strip which has a 15 amp circuit breaker. The 20 amp ckt was installed by the builder for charging a golf cart(I don't have one) so that circuit is the one for the shop gear. Now I know what I can run together and what not to run at the same time.
Thanks for everyone's input.
Bill V
I hope it is truly a 20amp circuit and not a 15amp circuit with a 20amp breaker.

If it is a 20 amp circuit, the wires from the main breaker panel to the wall outlet will be 12 gauge wire. Most easilt determined by inspection at the breaker panel.
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Post by wa2crk »

Dusty
Dedicated 20 amp wired with 12 gauge wire from the panel to the outlet. There was only one outlet originally but several were added later using metal boxes and metal conduit. I don't like using the plastic EMT in industrial areas.
Just a personal phobia.
Bill
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dusty
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Power Consumption

Post by dusty »

I thought I had reason to doubt but I retested three shop items this morning and I find that my equipment current demands are reasonably close to those already reported.

My Dust Collector demands 27 amps on startup and runs on 6.0 amps. The startup current is a momentary peak that drops back to run condition almost instantly.

My Power Station demands 22 amps on startup and runs on 8.5 amps. The startup current is also a momentary peak but does NOT drop back to run condition quit as rapidly.

My Mark V demands in excess of 30 amps on startup and runs on 6.5 amps. This startup current is also a momentary peak but that peak lasts noticeably longer than either the DC or the Power Station.

Significant to note: The circuit that I used for this test run is a 15 amp circuit (14 gauge wire and a 15 amp breaker). This is the circuit I use each and every day in the shop.

My Dust Collector and Power Station, when operated simultaneously draws 14 amps at run speed and well in excess of 30 amps during the startup peak. I cannot declare the actual amperage because my meter is peaked at 30 amps.

Caution: I do not recommend this combination be used. The startup peak is excessive and the run current is too close to the maximum
allowable.


My Dust Collector and Mark V, when operated simultaneously, draws a little bit less at 13.5 amps. The startup current for this combination is also in excess of 30 amps but is short enough in duration to NOT TRIP the breakers.

Caution: Again, I do not recommend this combination be used. The startup peak is excessive and the run current is too close to the maximum allowable.

Significant Observation: I did the tests that involved the Mark V with the Mark V set at both Low Speed and then at Saw Speed (low end) and witnessed NO NOTICEABLE difference in run currents. Because the meter is peaked during startup, I do not know what the maximum peaks were.

We routinely have discussions here on the forum about the problems users have when using a 15 amp circuit. I will never be convinced that there is not something else drawing current in addition to the Mark V. The other possibility is a marginal 15 amp service (loose connections, marginal breakers, damaged wire).

Changing to a 20 amp circuit seems to eliminate those problems but I would have to be convinced that increasing breaker size is not just masking the problem.

AND as Beeg would say - Lub It. As I would say - There is no such thing as excessive oiling. Well, you might have an unnecessary puddle of oil but the Mark V is not harmed.
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JPG
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Post by JPG »

wa2crk wrote:Dusty
Dedicated 20 amp wired with 12 gauge wire from the panel to the outlet. There was only one outlet originally but several were added later using metal boxes and metal conduit. I don't like using the plastic EMT in industrial areas.
Just a personal phobia.
Bill
Reminiscent of the 'thinwall' EMT/RMC argument of yesteryear.;)
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Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10
E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
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dusty
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Post by dusty »

wa2crk wrote:Dusty
Dedicated 20 amp wired with 12 gauge wire from the panel to the outlet. There was only one outlet originally but several were added later using metal boxes and metal conduit. I don't like using the plastic EMT in industrial areas.
Just a personal phobia.
Bill

I would use metal conduit and boxes but I also use a third wire ground.

Today's plastic conduit is probably just as safe but I am with you. I am more comfortable with the metal conduit. Be careful with all of the mechanical junctions though. If that conduit is your safety circuit, you don't want loose connections anywhere in the run.
"Making Sawdust Safely"
Dusty
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JPG
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Post by JPG »

dusty wrote:I would use metal conduit and boxes but I also use a third wire ground.

Today's plastic conduit is probably just as safe but I am with you. I am more comfortable with the metal conduit. Be careful with all of the mechanical junctions though. It that conduit is your safety circuit, you don't want loose connections anywhere in the run.
I am not so sure that glued plastic conduit is not safer than mechanically connected(compression rings) EMT, but especially so the single screw connections.

I agree, do NOT use the conduit itself as a ground. Ground each box with a grounding wire. I do have faith in the device yoke/box connection so prefer terminating the grounding conductor directly to the box. Easier to rough in and connect wires that way also.
╔═══╗
╟JPG ╢
╚═══╝

Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10
E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
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