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If you could jump into any other technical field, one that HVAC wound have prepared you for, what would it be?
Mine would be industrial/transmission high voltage electrical/ motor work, or process...

Sorry I misread your post. HVAC Has a high ceiling and variety of skills and training.

I will leave this because it's valid too...

I've had many offers for facilities work based on them...

707041

True but I thought he said this was a 15hp drive? They don't usually make those drives serviceable, including internal fuses- from what I know. If this isn't the case I would like to know.
So, make...

I believe in covering the basics. If the only thing you're seeing on the drive is an amperage, how can you be sure what % speed that is? The amp draw on blower motors are usually lower than FLA. ...

What's difference between this and running it in "hand" or "bypass" only the lack of overload protection. That's why you only do it temporarily or even for troubleshooting only.
VFD motors are...

Also want to add
- verify transducer reading by tapping a magnahelic or appropriate manometer in the same spot the sensor is.
-make sure you control wiring is protected (appropriately shielded)...

Do it the old fashioned way, connect power to motor. With wire nuts or just stuff the motor leads into the supply terminals with them.
Turn off the power of course

What's the amp draw in the motor if you bypass the VFD? You can start there to verify that the drive is not running at full speed. Blower motors can have low amp draws compared to nameplate.

The fact that you are having the earth fault on multiple drives on the same unit, with different motors tells me something systemic is going on. BUT...

I absolutely would have megged the motors to...

That's if you eat it everyday for a long time

Scramble it with eggs

Hear me out here...

My ex was a vegetarian. The only food I kept eatin after she was gone was SOYRIZO. it has all the flavor of chorizo and none of the garbage tissue and red grease oil of the...

Also to properly check the charge or charge it you need the condenser fan running all the time so you will need to bypass any speed control and try to do it when it's warm

if the power company says your power is clean, the only thing to do other than hire a 3rd party power analyzer and, if it comes out dirty, install expensive power filter banks, is to say ok it's...

What type of application/ motor is it on?
Probably not the drive's fault. You could be having winding condensation issues. ABB has a motor warming program you can put into the drive to prevent this....

" 700121 "

It's a line from Unforgiven. Because of the Little Bill reference. Because of the Gene Hackman reference.

Keep at least two bags- a very small one for doing PMs (just a few basic tools and a meter) and a full one for going into repairs with. After a while you may be surprised how much you can do with the...

Also, just to throw it out there, I haven't heard it yet...

CAPACITY CONTROL

understand that phrase and you will understand unloading

Any man who takes a shot at me, I'm gonna kill him.
I'm not only gonna kill him, I'm going to kill his wife. And his family. And all his friends. Burn his damn house down!

I can't believe my Gene Hackman post didn't get more love.
you guys need to watch more movies
Or get a better sense of humor...

Now read up on digital unloading and hot gas bypass...

Also, as mentioned above, don't get hung up on "norms" of solenoids being energized, de-energized (some operate off pressure). it varies!...

699911

Sounds like a bad drive.
Also, what were you using to read your voltage output, the drive display or a meter? If you used a meter you need one with a special filter to read drive outputs or your...

You may be right

You should always use di-electric unions the electrolysis happens in any water system.

Yeah...value...

When you hear "value" next to something what's the first thing CHEAP that comes to CHEAP mind CHEAP?

I'm sure you get it, I just can't rage enough at the idea because I've seen...

DO NOT PUT SCH40 PVC anywhere in the system, just because you can doesn't mean you should.
It's weak and doesn't respond well to hot/cold, there are specs, these temps (the heating temps are...

Don't you know nobody will talk to you unless you give SH and SC. this time it's actually applicable....

Just a good practice- soap your hose and manifold connections when doing a pressure test, especially if its going to be a long (hours or overnight) test. You may see some settling of the pressures...

I work almost purely medium to large commercial (some light stuff here and there, less and less thank god) for a well-established company with (mostly) major customers who aren't afraid to spend...

The whole premise of civil war was great... I have always wondered about how all these heroes are destroying entire cities fighting "bad guys" and no one seems to care (in the movie I like how they...

I hate pain-in-the-*** t bar ceilings.

Hopefully they went male PVC to female metal... A little better configuration for expansion tolerance. Still could leak of course.
Also lets hope they at least have sched 80 in there. I've seen...

It's about a minute more of brazing, not a big deal.
Maybe we can't all flow 45% as well, hats off to you buddy. Just a suggestion for those of us not as highly skilled.

Never had an issue.

Whatever gets the job done

Usually when I have to do this its on larger (2"+) connections. I find that the 56% I use (also tried the orange sticks... Meh) it doesn't flow around the joint very well. You kind of hAve to do it...

The 15% is used to cap the 56% or whatever you use, it's not bonding the metals. I always use that technique it works very well.

Test it on something else, the condenser fan maybe. If your meter is 3x off you will see it there too. Try another meter if you can get one.
Then you can rule that out

Also "ditto" is how you spell it
:ditto::gah:

:ditto::ditto:

Electrical! Motor theory, ohms law, how to use a meter for troubleshooting, ladder diagram reading (the real ones in the field, not the simplified classroom ones), using amp draw...

I work on drives <100hp but hope to work on the large ones eventually. The whole drive is powered down so I can't check the display.
Generally I wait at least 15min and check DC voltage before I...

will measuring voltage across DC bus give you an accurate gauge of residual charge left in the system?

Once the 50 is in the joint nice and good I like to cap it with 15. It helps smooth it out and fill in any rough spots.

20 CFM. Got her used for cheap, but she's still got some good years left. Just change the oil regularly.

Thanks for sacrificing a 15 ton compressor/system for curiosity

To clarify- are you doing this through a BMS system or is this something that is programmed in the Aaon controls?

First time I've heard of this, why would you take control of the digital scroll away from the unit's control? What level of better efficiency/operation is achieved?