Hey guys... I'm in the middle of a battle with the boss because when I try to tell him what I need he claims I don't know what I'm talking about. So I'm looking for some advice or help to make sure first that we're doing the correct thing and if I so happen to validate my thoughts along the way... great.
Our building has a 208 3 phase ungrounded delta transformer powering it up. We are building custom manufacturing machines that requires it to be 480v 3~. So we clearly need a transformer to step up that voltage. I did the math on all of the servo's which are going to be on this machine alone and they sum up to around 116amps of 3phase 480 FLA. The boss buys a used transformer which is a Delta Wye but it's a step down transformer so he has it wired in reverse so the 208 3~ goes to the WYE secondary which gives me 480 on the primary and then corner grounds the Delta on H3.
When I measure my incoming L1 from the transformer with respect to ground I get nothing (0.05 vac.) Then L2 is 480vac. Finally L3 is 480vac. Across any two I get 480. Well I was getting errors on my Kinetix servo controllers (5000 series) that I've never gotten before and my local distributor helped me deduce it's because I'm missing a phase since he corner grounded the delta. There is a pre-charge amplifier which isn't working correctly in the kinetix or something like this. They recommend that I change the transformer to a Delta/Wye step up or boost transformer as it's better anyways.
So I tell the boss that it's single phasing and i need to change out the transformer because it's the wrong type. Not what I asked for to begin with. He screams and yells and says I don't know what the hell I'm talking about.
Can anyone help me with this?
1.) Is the corner grounded delta the right configuration for an automation machinery which has sensitive servos.
2.) By grounding H3 the corner terminal of the delta, is it actually single phasing h1 and h2?
3.) Is a 208 3~ primary delta and a 480 3~ secondary WYE the right transformer to put in?
Thanks guys sorry for the long winded post
Our building has a 208 3 phase ungrounded delta transformer powering it up. We are building custom manufacturing machines that requires it to be 480v 3~. So we clearly need a transformer to step up that voltage. I did the math on all of the servo's which are going to be on this machine alone and they sum up to around 116amps of 3phase 480 FLA. The boss buys a used transformer which is a Delta Wye but it's a step down transformer so he has it wired in reverse so the 208 3~ goes to the WYE secondary which gives me 480 on the primary and then corner grounds the Delta on H3.
When I measure my incoming L1 from the transformer with respect to ground I get nothing (0.05 vac.) Then L2 is 480vac. Finally L3 is 480vac. Across any two I get 480. Well I was getting errors on my Kinetix servo controllers (5000 series) that I've never gotten before and my local distributor helped me deduce it's because I'm missing a phase since he corner grounded the delta. There is a pre-charge amplifier which isn't working correctly in the kinetix or something like this. They recommend that I change the transformer to a Delta/Wye step up or boost transformer as it's better anyways.
So I tell the boss that it's single phasing and i need to change out the transformer because it's the wrong type. Not what I asked for to begin with. He screams and yells and says I don't know what the hell I'm talking about.
Can anyone help me with this?
1.) Is the corner grounded delta the right configuration for an automation machinery which has sensitive servos.
2.) By grounding H3 the corner terminal of the delta, is it actually single phasing h1 and h2?
3.) Is a 208 3~ primary delta and a 480 3~ secondary WYE the right transformer to put in?
Thanks guys sorry for the long winded post
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