480v 3 phase - Canada - Issues ??

[davelashley]

Hi,

I’m an engineer in a small company, we normally supply skid mounted mixing and pumping systems to the USA. We normally design the systems, each one custom engineered, to have one main incoming feed no matter how many sub skids we have. The main feed is typically 480v 3 phase around 130 Amps. We have 3 phase motors and 3 phase heaters on the skids.

We now have a job to supply some kit to Canada. Originally everyone was happy with our kit being 480v 3 phase. Now they have come back and said they can supply 600v 3 phase. We don’t really want to redesign all our kit for 600v so I’m thinking of suggesting we just “simply” insert a 600 to 480v transformer between the supply and our kit.

My question is – Is this acceptable in Canada, is there a problem supplying a 480v piece of kit in to Canada? Do we have to be aware of any special requirements?

I have a copy of the Canadian Electric Code on order but this change has happened so fast I have come here for initial feed back on our transformer idea.

Thanks for any help or suggestions.

Dave

 

[LionelHutz]

480VAC is only used in a few areas in Canada. I don't know the details of what is supplied on your skid but the only real issue is to confirm that spares for the components supplied wouldn't be easier to source if they were operating on 600VAC.

Of course, you will have to ensure the transformer is acceptable to the end user.

 

[majesus]

When we sometimes order UPS systems for our Canadian clients, the manufacturer will put a 600V to 480V XFMR on the front end.

I don't see a problem of doing it. It probably does make more sense then trying to redesign the entire product with new parts rated at 600V.

I'm sure the client won't be thrilled as now they have an XFMR to deal with... But if it that is their only option, I'm sure they'd accept it.

 

[waross]

At one time in western Canada, when the utilities were supplying 600 volts and customers were sticking with 480 volts auto transformers were used in open delta.
It only takes two transformers and is quite efficient.
The transformers would typically be installed between the main disconnect switch and the main distribution center.
You won't have 277 volts available and any single phase loads must be connected line to line on 480 volts.
respectfully

 

[jraef]

I agree that you can do it, but you may get resistance because of the transformer. it will also mean that replacement motors will be less likely to be in stock for them at some point in the future when they need to fix something.

But why not just supply a 575V system? All it would mean is a change in the motors you buy, the overload settings and a different control power transformer. All of your motor starters and contactors for the heaters will be fine because the current will be lower. Every OEM I know of who want to sell into Canada does this, it's called good customer relations. Don't make a mountain out of a mole hill.

 

[Gianoli]

“My question is – Is this acceptable in Canada, is there a problem supplying a 480v piece of kit in to Canada? Do we have to be aware of any special requirements?”

No, there should be no special requirements required to supply 480 Volt equipment in Canada. I live and work in Western Canada and 480 Volt systems are still used extensively. The company I work for has a huge amount of 480-volt equipment installed and all new facilities still utilize the 480-volt system.

“We don’t really want to redesign all our kit for 600v so I’m thinking of suggesting we just simply” insert a 600 to 480v transformer between the supply and our kit.”

I have to question how much “redesign” would be required to make your present equipment compatible with a 600-volt system. While I don’t know the details of your particular system most 480-volt motor control equipment is basically identical to 600 volt equipment. Unless your doing something out of the ordinary a voltage change from 480 to 600 should not be a big issue from a design stand point.

 

[davelashley]

Thanks for all the feed back – it is definitely food for thought. Half say go with the transformer and half say redesign. The twist to this I guess is that we don’t have a 600v supply to our building. We have to fully functionally test the kit here (FAT Test) before it ships.

Our equipment is based on some unique pumping technology and is used to mix, pump and sample highly radioactive waste which is typically kept in underground storage tanks. We reconfigure our equipment to meet the needs of our customer and build a bespoke system just for them. Long term spare parts is not usually an issue as our kit will be used to empty the tank it was designed to then be disposed of. This can take anything from 3 days to 3 months. As it deals with high active waste we fall under the NQA1 quality requirements and as most of you know – now were talking mountains and mole hills! For NQA1 we can only purchase equipment from our company approved vendor list, if a 600v equivalent exists at the same vendor then we are in the clear. We do have a certain comfort level with the kit / components we typically supply, we know they work and we know they are reliable which all helps in this line of work. The big 3 phase 480v things are a fan motor and controls, a duct heater and thyristor, and a large peristaltic pump and controls. We also have a 240v HVAC system in the control container. We have put 8 weeks of time in to the preliminary design which has to be submitted on Friday, all based on the 480v supply. The 600v requirement has come from the inability / reluctance of our customer to locate a 480v portable generator to run the kit literally in the “field”!

Thanks for your time and responses, like I said food for thought.

 

[itsmoked]

Now where did I put my transformer?

I can see the customer thinking, "This whole thing is temporary I hate to buy a transformer too."

How about leasing/renting them one?

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[waross]

I agree with itsmoked.
If you must buy a transformer consider two 120:480 volt transformers, rated for buck boost service connected in open delta boost. The 120 volt windings must be rated for the current at 600 volts. This gives a much smaller, cheaper installation than a complete three phase transformer.
I have used this connection many times for at least 3 different customers with no problems.
Can you install the transformers in the customers plant and supply 600 volts to your equipment without the regulatory hurdles? Possibly under the same chapter that allows a portable generator.
If you do change your kit to 600 V, the transformers could be used to shop test the kit at 600V.

respectfully

 

[Morquea]

Your client final decision will probably be based on cost and delay at the end.

So show them many options like:

Estimated cost and delay for 480V design with bought transformer.
Estimated cost and delay for 480V design with rent transformer.
Estimated cost and delay to redesigned your skid at 600V.

And let them think about it.

Respectfully.