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Old 05-15-2017, 01:57 AM   #41
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I been thinking why not boost the incomming source to 480 volts ( 200 amp ) then use the transfomer to down step back to 208 then he can get full 400 amp on 208Y120 so could kept the 2 inch conduit.
That WOULD be elegant.

STILL, the disco would have to be 'addressed.'

I'd jerk it and replace it with a suitable MAIN C/B.

The joint needs to be re-engineered.
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Old 05-15-2017, 09:06 AM   #42
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2inch conduit .,, daymm .,, Ok now that fun just start now .,,



coconut rum time ??



the biggest issue is the POCO conductors all it depending on where it come from if from outside then it is not too bad but if it was ran under the building that can get a headache there.



I will let WronGun answer that question.


This is the main concern I brought up to the Owners , that 2" pipe run needs to be traced... the panels are located at the very back of the building

As you can see if this was ran from the front we have a big problem

At this point I can see how 480V with a Tformer may be our only option





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Old 05-15-2017, 09:47 AM   #43
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This is the main concern I brought up to the Owners , that 2" pipe run needs to be traced... the panels are located at the very back of the building

As you can see if this was ran from the front we have a big problem

At this point I can see how 480V with a Tformer may be our only option
It don't matter which way the uility run from.,, there is always a solution for that.

But yes please do trace that uility conductors and see where it do run so you can able figure out where it run and may ran to the transfomer pad or to the pole in the back if latter you may get lucky depending on the distance from that location to the uility source useally either pad or pole depending on how it strung.

but if you going to use the transfomer route the transfomer size for that size of useage you will need at least 150 Kva transfomer that is kinda common item but little lead time to find it.
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Old 05-15-2017, 04:15 PM   #44
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It don't matter which way the uility run from.,, there is always a solution for that.



But yes please do trace that uility conductors and see where it do run so you can able figure out where it run and may ran to the transfomer pad or to the pole in the back if latter you may get lucky depending on the distance from that location to the uility source useally either pad or pole depending on how it strung.



but if you going to use the transfomer route the transfomer size for that size of useage you will need at least 150 Kva transfomer that is kinda common item but little lead time to find it.


I will definitely be checking with the inspector about all of this .... I don't recall ever installing transformers outside of enclosed electrical rooms within a building

Regardless I'm going to first see if I can bring something in overhead

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Old 05-15-2017, 05:31 PM   #45
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That Service Lateral pipe has to terminate underneath some ( pad mounted?) Poco transformer... or run up some pole.

75kVA Poco pad mount trannys are pretty common, and would be expected if this is a free standing building.

In which case, the Poco could swap it out ( for $$$ ) to give you your 480Y277.

&&&

The big can needs to be transformed into a CT cabinet, with the meter left as is. (to Poco standards)

The fused disconnecting switch has to go entirely, perhaps re-used on the secondaries of your 480 to 208Y120 transformer. ( Mount it directly to the transformer body -- on the side. ) This space then would permit a 200A 208Y120 MLO panel. (It could even be the existing one, which will have to come off the wall to be remounted. Its space is needed for the 200A 480Y277 MAIN panel.)

You could go with twin 75kVA transformers off of the new 200A 480Y277 MAIN panel.

Twin 200A 208Y120 panels would give you plenty of breaker spaces. One of those panels could be the existing one, moved over and re-mounted.

The new MAIN panel would have a MAIN C/B... and could power lighting circuits at 277VAC, etc.

75kVA transformers are small enough that it's often practical to mount them directly overhead on some frame that is also secured to the wall. CBU is usually too weak to hold them without auxiliary steel framing.

Also consider setting a gutter, below the transformers and above the panels, so that you can pick up all of the old EMT runs cleanly and quickly.

The above scheme would let you re-use components and not hog up too much space.
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Old 05-15-2017, 05:44 PM   #46
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I will definitely be checking with the inspector about all of this .... I don't recall ever installing transformers outside of enclosed electrical rooms within a building
I have done that pretty often by installing the transfomer outside of electrical room espcally with very large area.

serveal reason why I do that is I can bring 480 volts circuits further and use the transfomer to branch out the local circuits as it need to be.

and yes Tesla did bring up few good points and I done simuair way what he is describing.

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Regardless I'm going to first see if I can bring something in overhead
Try to see you can bring it in overhead if possible if overhead clearance is there otherwise run a new lateral run with much larger size . something sized at least 600 amp 208Y120 volts otherwise bring in 600 amp 480 volts service then use the transfomers as it need to be.

Note some of the kitchen equiment some can switch over to 480 volts ., if so I would go that route if possible espcally with high power hogs units.

Keep us posted on the progress what ya got there.
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Old 05-15-2017, 06:01 PM   #47
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I will definitely be checking with the inspector about all of this .... I don't recall ever installing transformers outside of enclosed electrical rooms within a building

Regardless I'm going to first see if I can bring something in overhead

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I've done this in shopping malls all over New England, right on the stockroom floor of the tenant space.

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Note some of the kitchen equiment some can switch over to 480 volts ., if so I would go that route if possible espcally with high power hogs units.
This is a great point. Does your customer own this stuff already? If not maybe they could look at getting more 480V equipment.
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Old 05-15-2017, 06:09 PM   #48
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I've done this in shopping malls all over New England, right on the stockroom floor of the tenant space.







This is a great point. Does your customer own this stuff already? If not maybe they could look at getting more 480V equipment.


Yes , they do own the equipment all
Of which is 120, 240, and 208.

I will start to draw this out as soon as I get more info. Ive spent the last 11-12 yrs following prints, so putting this together will be new to me.

I highly doubt they expected this , and I'm sure they signed the lease without ever thinking if they have enough power.


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Old 05-15-2017, 06:16 PM   #49
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Yes , they do own the equipment all
Of which is 120, 240, and 208.

I will start to draw this out as soon as I get more info. Ive spent the last 11-12 yrs following prints, so putting this together will be new to me.

I highly doubt they expected this , and I'm sure they signed the lease without ever thinking if they have enough power.
I would go with Wye system for very obvous reason.,, but try to come up couple alterante plans so if the POCO and cost is not too bad I will use the latter route and use that for expandision so that way the customer dont have to heavy up twice on the dammed service. ( trust me on that some customer found out in hard way )

That is very common with alot of customers signed in the lease and not really relaized about the service size that useally bite their butt pretty hard if they are not aware of it.
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Old 05-15-2017, 08:34 PM   #50
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Once they see the tab, don't be too surprised if they back out of the lease.
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Old 05-16-2017, 11:14 AM   #51
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Once they see the tab, don't be too surprised if they back out of the lease.


I will not be surprised. Unfortunately, they have already done so much work in the office areas. Their options are limited


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