What I would do and what I would advise on a forum could be two different things.
That style of device and circuit is intended for use on 208V equipment only as it has a ground and no neutral. However, they are used for domestic appliances such as clothes dryers and ranges that have 110V lamps in them. However, that is in a residential setup on 240V.
I don't believe that to be a legit setup for stage gear. Maybe some of the other guys know more about that style plug on a 208V system. To be legit it would probably need to be a 4-wire setup with separate ground and neutral.
There could be liability connecting to that - again, let's see what the other guys think about it.
Hypothetically speaking, would I be able to make an adapter that taps the neutral and a hot leg with a clamp lead running to the exposed ground wire above the receptacle and would I still get the 50a current rating? I know this is sketchy but I'm just curious for education purposes.
Also, the wiring diagrams I saw online showed their should be 245-250v between the phases rather than 208v I measured.
The amp is setup for single leg service even at 230v so you are out of luck. CPC 45 A AMP connector is on the back. Please refer to page 5 section 4:3 for these details. The wiring is H-N-G. If it was a four wire connector at the venue you could accomodate this. Don't even consider a bootleg ground.
Please also not downstream protection requirement from the manual "With K6, K8, K10 and K20 a sectioning breaker between the mains connections and the amplifier must be installed inside the rack cabinet. Suggested device is 32A/250VAC, C or D curve, 10kA."
The venue doesn't have any other high current connections? I usually go hunting in the kitchen. If not you will have to get a generator.
Also, the wiring diagrams I saw online showed their should be 245-250v between the phases rather than 208v I measured.Douglas, you're seeing 2 legs of a 3-phase system.
ASSuming you can make a legal connection, my experience with Powersoft is that they run on anything.
My K20 run fine on 2 hot legs (230V between legs) or hot-neutral (230V between hot-neutral).
Interesting, and is there such a thing as +phase and - phase? Does it matter which phase goes to which terminal and is there a way to test that with a multimeter?
Also in this image:
https://bit.ly/3JQm1wt
What is going on what that ground wire running to the receptacle? What would that be connected to?
Second, Douglas, your question of a separate ground shows you payed attention to what each wire does. Code says all wiring must be enclosed so Code says no. I have seen what you are asking, done in locales where permitting and inspections are lax. That should not be considered an endorsement, but an observation.
| Power Supply: | Universal, regulated switch mode with PFC (Power Factor Correction) |
| Nominal power requirement: | 100-240 V ±10%, 50-60 Hz |
| Operating voltage: | 90 V – 264 V |
Bottom line: my understanding of the codes is that the NEMA 10-50R is listed to provide two hots and a ground, which would be sufficient to supply the Powersoft K20 DSP. Bear in mind that overcurrent protection must be sized accordingly.
I haven’t seen phases labeled +/-. I’d avoid that because of the connotations to DC power. Usually in my experience it’s legs 1-3 or by color.
For wiring on a system with equal phases (no wild leg etc) it doesn’t matter which leg hits which line terminal on your wiring device. The point is the voltage differential created between the two legs and/or between line and neutral.
Thanks for all the great info everyone.
I plan on expanding my power distribution inventory, but to get by for this gig (assuming I can verify the powrrsoft will take two hot legs in place of a hot and a neutral) is to make an adapter from 10-50P to L6-20 but instead of connecting the ground to the neutral, clamping the ground conductor to the breaker panel chassis or exposed grounding conductor. Is this excessively sketchy/illegal or will it be safe?
Alright everyone,
So I talked to Powersoft support and they corroborated what some said on here: the K20 will operate fine with two hot legs across the terminals rather than a hot and a neutral, and, if the neutral is bonded to ground I can substitute the neutral of the receptacle for the grounding conductor. So I can essentially make an adapter using all three conductors of the 10-50R directly into the K20 (this isn't considering the 30 amp breaker I will need ofcourse.
Of course you CAN do that, but what you are doing is NOT code. You should strongly push for the venue to install the PROPER connector for this type of use.