Hoist Motor Power

The second part is correct, ALWAYS measure leg to leg, and legs to neutral (and I also do legs to ground)
BUT, the first part is incorrect. (which is why we always measure)

On more than one occasion, I have seen 5-cam outs as high leg delta... 240v phase to phase, 208 phase to neutral on one leg, and 120 phase to the other two legs.
By code, the 208 leg cam would be orange instead of red, but can often be hard to discern.... and not everyone follows code... especially with older installs.
two of the times I ran into this issue were rental generators and transformers, where the transformer had been configured as high-leg, but was not marked.
The third time was a TV gig in an old warehouse that had used high-leg for the previous tenant, and we were the first production in the space.

This is why I did say that in any installation outside of an actively running theater-only complex to not ever assume the electrician before you knew or cared about the difference between delta and Wye.

You are correct that certain industrial/entertainment generators which are field switchable between 208/240 will have the 5 standard Wye cam outs presented, the installed panels I've seen will only have the Blk/Red/blu/wht/grn in the Wye service installations.

As far as measuring the outputs it is a good idea, and I did neglect, to mention leg to ground - but also neutral to ground to be sure you don't have a floating neutral system.
 
@Gobokat Quoting your recent post: "a lower presented voltage (208 vs 240) will mean that the equipment will draw more amps".

Are you suggesting an applied voltage of zero volts will cause connected gear to consume infinitely high current?
In the mid 1990's, I had a co-op student who leapt to this incorrect assumption. I explained if his logic were correct, black-outs would be prohibitively expensive. @TimMc Care to comment?
Toodleoo!
Ron Hebbard
Negative voltages will result in a reversal to the space-time continuum. Alternating currents need not apply. That's my story and I'm sticking to it. :twisted:
 
1) if you see 5 cam outs (Blk, Red, Blu, Wht, Grn) it HAS to be WYE (120/208) power
I must disagree with this part of your statement, the industry standard of black red blue for 120/208v power is not mandated anywhere in the NEC. The NEC does not even cover any color code other than reserving green, white, gray, and orange for grounds, neutrals, and high legs respectively and states the if you use a color code for identification you may only use those colors for that. Orange is a little odd in that it is reserved only if the building has a high leg.
While black red blue and brown orange yellow is an almost universal practice across the electrical industry, it is not code. It is however common enough that people get complacent and start assuming. It only takes one odd installation to ruin your day.

And to further muddy the waters in Canada they use black red blue for 575v as well as 208v

And in concurrence with the second part of your post, always meter everything before you connect.
If you do not know how to safely use a meter to check voltages and determine what type of system you are dealing with from those readings you are not qualified to be connecting power at that scale. Stop and get some one who is.

Dover
 
Hey guys, been away from here for few days. I appreciate the discussion! This is exactly what I hoped for.

@Gobokat i do have a controller that will be used to control the motors.

I almost always carry a DVM in my bag pack. it seems logical to take measurement prior to connecting any equipment and hearing from you guys, it seems like I should always check before connecting.

@Dover I see what you mean about assuming. I am thinking, the color/voltage can be different but a 5 wire system translates to a 3-phase, WYE configuration, yeah? i understand the Concept of High leg so again, metering would help clear things up.

i see what the point @Gobokat making, most of the power distro I have seen has the Blue, Red, Black, White, and Green Connection points. Furthermore, the few times i have seen the tie in connections at a hotel, they have been of the same (BRBWG) color. i can't say much about the voltage but, just what i have observed.
 
Hey guys, been away from here for few days. I appreciate the discussion! This is exactly what I hoped for.

@Gobokat i do have a controller that will be used to control the motors.

I almost always carry a DVM in my bag pack. it seems logical to take measurement prior to connecting any equipment and hearing from you guys, it seems like I should always check before connecting.

@Dover I see what you mean about assuming. I am thinking, the color/voltage can be different but a 5 wire system translates to a 3-phase, WYE configuration, yeah? i understand the Concept of High leg so again, metering would help clear things up.

i see what the point @Gobokat making, most of the power distro I have seen has the Blue, Red, Black, White, and Green Connection points. Furthermore, the few times i have seen the tie in connections at a hotel, they have been of the same (BRBWG) color. i can't say much about the voltage but, just what i have observed.
Up here North of little Donnie's walls, we often see reversed sex cams on neutral and ground.
On your side of the walls, 120 / 208 is common with 277 / 480 being your next higher voltage.

Up here North of little Donnie's walls, 120 / 208 is common with our next higher voltage commonly being 347 / 600.
We rarely see 277 / 480 outside of industrial applications.
Toodleoo!
Ron Hebbard
 
@RonHebbard I picked up few adapters in case I run into reversed genders for Ground and Neutral! thanks for the heads up. Good Information!!
Reversed gender ground and neutral are sometimes required by local Code enforcement. The NEC permits 3 (I think) different ways to enforce connection / disconnection order and means of preventing incorrect connections. The lowest is signage (and training to make the operator "competent"), the preferred methods make incorrect connection physically impossible. Reversing gender on ground and neutral is easy to do and costs nothing extra, but the gold standard is used of separately keyed connectors to prevent misconnection of all conductors, with physical interlocks to enforce connection order.
 
I am thinking, the color/voltage can be different but a 5 wire system translates to a 3-phase, WYE configuration, yeah?
For the most part, yes, unless as you say it is a high leg delta. It would be extremely odd for a neutral to be pulled out to cams on a high leg system but not impossible that someone has done it for some reason. Very few high leg systems are even installed anymore. The point I was driving at was that 5 wire is almost always a wye, what voltage is that wye. Black red and blue cams are no guarantee that it is a 120/208v system. I had one project where I was using a 480v isolation transformer with the taps set as far as they would go to derive as close to 400/240v power as I could for some European equipment we had. It was still phased brown orange yellow but was not something you wanted to hook your 480v motors up to.
 

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