Enough of COVID...what are you doing to the house? | Page 404 | GTAMotorcycle.com

Enough of COVID...what are you doing to the house?

GreyGhost said:
Thanks for the link.

Motor is marathon d013. 3 hp. 14 fla.
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I'll admit I'm a bit rusty on sizing, I use my yellow code manual and rules of thumb I learned from electricians who helped me out over the years. I typically use 750w/hp for motors, which would be 2250w for 3hp. @200v that's about 10A. I believe the FLA is the max amperage before the motor can take when voltage drops -- so draw 14A the line voltage would have to drop below 160VAC.

OK, so you're looking at 2 things, conductor size and breakers. Your conductors must take 1.25 the ampacity of FLA, or 17.5A which is within the technical limit of NMD90 14ga, however, I think most electricians would spec 12 ga. The breaker should not exceed the limit of the conductor, which I'd set at 20A.

Ampacity Chart | Wire & Cable Technical Resources | Lapp Tannehill - this is a nice chart. Typically we use 90C l(NMD90), so you 14AWG will handle up to 25A).
 
GreyGhost said:
I'll add a filter. I am trying to avoid pulling the head to clean out existing gunk. Valves seem similar to Reed valves. Basically check valves. No apparent mechanical operation.
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I have been running a 3 hp compressor on 14/2 and a 15 amp breaker for 10 years never had any issues. It runs about 3 hrs a day on for 8.

Sent from the future
 
I bought mine
GreyGhost said:
If you want most of the liquid, the first link should work and is cheap (but requires a 24vac source which you can buy for cheap or steal power off a doorbell or alarm panel). If you want a more thorough purge, the second one will get some mist out and a lot more of the water.


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I bought mine for $2 in the Surplus aisle of the Newmarket PA for $2, it's 120VAC with a 3/8" MIP in and out, I connected it to a stupidly simple refrigerator defrost timer. When the controller starts the compressor, the timer starts counting, when it reaches 8 hours of run time, it fires the solenoid for a minute. Keep my air supply pretty dry.

I'm building a smarter controller for my new compressor, I really only need it to fire once a week for 2 minutes.
 
Scuba Steve said:
I have been running a 3 hp compressor on 14/2 and a 15 amp breaker for 10 years never had any issues. It runs about 3 hrs a day on for 8.

Sent from the future
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I'd bet you are fine forever with nothing else on that circuit -- you would need the line to drop below 150vac to trip the breaker.
 
@GreyGhost is it hard wired or does it have a plug?

No need to over think it and buying new wire no need to cheap out. If it says 14 FLA you can go with 12 gauge which is rated at 20 amps but really 16 amps (80%) continuous in this context. Depending on what else you may want to do and length 10 gauge may add some future proofing... Next question is there a need for neutral now or in the future for three vs two wire. IF it is two wire 240 VAC and you go 12 gauge go with the red sheathed wire which has a red and black (both hot) instead of yellow sheathed for extra points...

Over thinking a bit more.... 3 HP is 2,238 watts, nominal voltage today is 240 VAC (was once 220 VAC). At 240 VAC (ignoring PF) that is 9.3 amps, at the old school 220 VAC that is a little over 10 amps, then factor in the PF and possibly efficiency...

I would not lose any sleep over 220 VAC rated on modern 240 VAC circuits.... You can check your voltage, I am at 247 VAC at home....
 
Mad Mike said:
I'll admit I'm a bit rusty on sizing, I use my yellow code manual and rules of thumb I learned from electricians who helped me out over the years. I typically use 750w/hp for motors, which would be 2250w for 3hp. @200v that's about 10A. I believe the FLA is the max amperage before the motor can take when voltage drops -- so draw 14A the line voltage would have to drop below 160VAC.

OK, so you're looking at 2 things, conductor size and breakers. Your conductors must take 1.25 the ampacity of FLA, or 17.5A which is within the technical limit of NMD90 14ga, however, I think most electricians would spec 12 ga. The breaker should not exceed the limit of the conductor, which I'd set at 20A.

Ampacity Chart | Wire & Cable Technical Resources | Lapp Tannehill - this is a nice chart. Typically we use 90C l(NMD90), so you 14AWG will handle up to 25A).
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Some of the difference with your math is you are assuming output power equals input power. To get 3 HP out of the motor, you need more than 2250 watts in. In my case, efficiency is 78.5% so 2250 watts out needs almost 2900 watts in to the motor.

It's looking like I don't need to use the 80% derate because it is just a motor load. I have 12 ga thhn which is rated for 20 amps continuous in conduit. Circuit breaker at 30A provides the protection without inrush trips (allowed to go up to 35 amps by CEC or higher if it won't start).
 
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backmarkerducati said:
@GreyGhost is it hard wired or does it have a plug?

No need to over think it and buying new wire no need to cheap out. If it says 14 FLA you can go with 12 gauge which is rated at 20 amps but really 16 amps (80%) continuous in this context. Depending on what else you may want to do and length 10 gauge may add some future proofing... Next question is there a need for neutral now or in the future for three vs two wire. IF it is two wire 240 VAC and you go 12 gauge go with the red sheathed wire which has a red and black (both hot) instead of yellow sheathed for extra points...

Over thinking a bit more.... 3 HP is 2,238 watts, nominal voltage today is 240 VAC (was once 220 VAC). At 240 VAC (ignoring PF) that is 9.3 amps, at the old school 220 VAC that is a little over 10 amps, then factor in the PF and possibly efficiency...

I would not lose any sleep over 220 VAC rated on modern 240 VAC circuits.... You can check your voltage, I am at 247 VAC at home....
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My power is really hot. Too hot. 253V right now. Plan is 12ga thhn in conduit with a 30A breaker. Run is <20'.

EDIT:
It current has a cord and plug. 15A rated plug. No signs of any issues. It will likely be hardwired when my install is complete. Location will be relatively hard to access, no good reason to have a plug. That also replaces the cord that may not be 12 ga (I didn't bother to check).
 
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crankcall said:
At 253 I’m surprised you aren’t cooking any sensitive electronics?


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Haven't yet. Lots of knocking on wood. Tested with a few different quality meters that agree (but haven't been recently calibrated although they are pretty stable). I have considered seeing if hydro one would go down one tap as that is pretty spicy but I haven't bothered calling them. They have worked on the transformer while I was here so presumably they measured when they were done. Maybe they assumed more drop between the transformer and first house?
 
GreyGhost said:
Haven't yet. Lots of knocking on wood. Tested with a few different quality meters that agree (but haven't been recently calibrated although they are pretty stable). I have considered seeing if hydro one would go down one tap as that is pretty spicy but I haven't bothered calling them. They have worked on the transformer while I was here so presumably they measured when they were done. Maybe they assumed more drop between the transformer and first house?
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That's a LOT of assumptions for your local hydro workers...I'm happy with mine as they've been awesome when I was doing my meter push out.

But assuming they did / check things...asking for disappointment.
 
GreyGhost said:
My power is really hot. Too hot. 253V right now. Plan is 12ga thhn in conduit with a 30A breaker. Run is
EDIT:
It current has a cord and plug. 15A rated plug. No signs of any issues. It will likely be hardwired when my install is complete. Location will be relatively hard to access, no good reason to have a plug. That also replaces the cord that may not be 12 ga (I didn't bother to check).
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Mine is running at 208 2 phase of 3 phase supply

Sent from the future
 
crankcall said:
At 253 I’m surprised you aren’t cooking any sensitive electronics?


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Oof 255 now. If I checked at 3am, think I could get 260? I guess a call to hydro is in order.

Over 254 counts as extreme service and by their own documentation warrants an emergency service call. Of course, they have no good way of notifying them of this online and you need to call during business hours. I'll take a pick of dmm around midnight so I have some documentation when they don't believe me.

Now, is my meter accurate to one volt when it was last calibrated long ago? They are pretty stable but that may be asking a lot.
 
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Crap. I had 3-4 multimeters with me today. 3 are Flukes. Could have measured with them while I was up there today.
 
oioioi said:
Crap. I had 3-4 multimeters with me today. 3 are Flukes. Could have measured with them while I was up there today.
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My main one is an 87V. I also tested with a Klein et600 which is obviously not as good but is much newer. They agreed within a tenth of a volt. Odds are the measurement is accurate.
 
Chances are high that they are correct.
I would bet $20 that and old analog meter would read with a couple of volts of the current readings.
 
At 253 , meters that are plus or minus 5% of each other won’t matter , you’ve still got hot hydro .


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crankcall said:
At 253 , meters that are plus or minus 5% of each other won’t matter , you’ve still got hot hydro .


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Holy hell.

I called hydro. First they asked if I was experiencing issues and when I said no, they asked why I was making a report. Then they asked me if I checked the breaker. wtaf. If I had magic voltage increasing breakers, I wouldn't need Hydro One. He needed an answer to that question before we could proceed. Facepalm. Ticket submitted. We'll see what happens.

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