Isolation Transformers

[OddJohnny]

Looking to start servicing power tools. I’m looking for isolation transformers for 415/230/110V either separately or combined/tapped, above 5KVA. I’m based in the UK. Any suggestions on where I can source?

[stj]

415 is 3 phase 240v
240 is negative bonded to ground,
110v is usually center tapped 55-0-55 to ground.
so know what your actually working with.
for 110 just get a yellow site transformer,
240 i wouldnt bother frankly - it will kill you through a transformer anyway - just use an RCD.
a transformer if you did get one would defeat an RCD anyway.

do you have 3phase?
last person i heard of having it installed got charged over £7000 for the install.
better to use an invertor from 240

[OddJohnny]

Thanks for the reply.
I'm currently in the planning phase for a new business. Much of the work I'll be doing is for local government & they require ISO. H&S has to be independently verified to obtain ISO. Most of the work will be PAT failures. Trying to avoid RCDs as I've found live testing can cause tripping. Risk assessment will allow non-RCD outlets provided use of isolation transformer(s) & PPE. I do have 3ph at the unit but 1ph currently supplied. Obviously, I'd like to spend as little as possible, but it wouldn't be worth more than £2k to me. Manufacturers direct are more than double that.

Step up transformer I hadn't really considered tbh.

If there are recommendations for makes/models & sources of reliable transformers, I'd be most grateful.

Many thanks.

[stj]

government agencies are stupid.
isolation transformers wont limit the current in any way that will prevent death or a big bang and fire.
if your dealing with PAT stuff then 99% of it will be bad cables - the rest will be psu damage related to wrecked metal-oxide varisters because the stupid fucks dont know you arent supposed to pat-test electronic supplies or devices fitted with them.
you also arent supposed to pat anything with removable cables or any fixed equipment.
PAT = PORTABLE appliantce test.

no legal requirments for it even.
it's a big fucking scam and a lot of "test" companies get big money damaging stuff so they can put a little green sticker on it.
better read this (government) link,
and never test equipment with more that it's rated voltage - if you insulation-test at 500 or 1000v you do slow damage to the surge suppressors inside
https://www.hse.gov.uk/electricity/f...ce-testing.htm

use an RCD for final test - they dont "false trip"
if they trip the device has a ground fault

[petehall347]

pat testers should not trip the power line unless its faulty in itself . think mine is fitted with an isolation transformer .

[stj]

i dont understand how you trip an rcd pat testing,
the pat test device is battery powered - the device under test is not connected to power.
unless we are dealing with a total noob doing ground current tests to a device while it's wired-in.
i would throw such a person through the window and tell them if they come back it will be from the roof next-time.
a stupid act like that can cause a plasma-arc explosion.

all this miss-placed electrical testing is a joke anyway from a government that removes safety requirements for food and pharmacuitical products!
and the people doing these tests dont need any electrical knowlege or skills - just a £300+ tester and a roll of stickers!

[petehall347]

i dont understand how you trip an rcd pat testing,
the pat test device is battery powered - the device under test is not connected to power.
unless we are dealing with a total noob doing ground current tests to a device while it's wired-in.
i would throw such a person through the window and tell them if they come back it will be from the roof next-time.
a stupid act like that can cause a plasma-arc explosion.

all this miss-placed electrical testing is a joke anyway from a government that removes safety requirements for food and pharmacuitical products!
and the people doing these tests dont need any electrical knowlege or skills - just a £300+ tester and a roll of stickers!

my pat tester is mains powered .. Clare A255 .. cant see how a load test can be done otherwise .
https://flameport.com/documentation/...Clare_A255.pdf

[sam_sam_sam]

https://flameport.com/documentation/...Clare_A255.pdf

Very interesting article about safety testing

[stj]

flameport? john ward?
that guy has a youtube channel, he thinks the electrical regulations (that constantly change and are partial bs these days) should be treated like the bible!

[OddJohnny]

PAT is a requirement under Electricity at Work Regulations, although this is an implied requirement rather than specified. If you have employees that get killed/seriously injured by faulty equipment & you don’t have all the necessary H&S in place, you’re going to jail. Employees need to be trained on a piece of equipment before they can use it. This involves checking the equipment for faults prior & post use, reporting systems for faults/suspected faults, regular maintenance & checks by a qualified person. It’s only criminal not to have done it if there’s an accident involving faulty equipment. Lots of insurance companies require PAT as part of their policies. Government & agencies are sticklers for it, many requiring that a valid PAT be produced before use of the equipment is permitted on their sites with many larger businesses following suit.

It’s a huge industry with potential to expand &, although around 95% of failures can be found visually inspecting equipment, each failure also brings additional business in the way of fixing &/or procurement.

PAT is undertaken on site by us, but the failures are removed back to our workshop for analysis & reporting back to our clients. Testing & repairs in our workshop sometimes require the appliance be live &, given the items are faulty, likely to trip MCBs/RCDs, etc.. Live & under a thermal camera is the quickest way I’ve found to identify shorts. The independent H&S consultants we use will allow faulty equipment to be made live, but only if it’s via an isolation transformer, with PPE & under strict conditions. We have to be in compliance with the H&S to achieve ISO status needed to maintain the contract.

For the amount of work that failure repairs produces at the moment, it’s not worth spending £5k+ on a custom transformer station.

As for experience, I’ve almost 20 years experience in electrical & PAT, qualified as an electrician to C&G Design & Verification. Person’s undertaking PAT are required to be suitably qualified &, although a monkey with some stickers could do a test, if the equipment were faulty & someone was injured, there’d be a lot of uncomfortable questions to answer that would almost certainly end with a minimum of a fine & possible criminal conviction.

Dismissing PAT… it’s highly profitable with little in the way of overheads. The work is easy & clients are professional. Businesses not doing it are liable to damages & in worst case scenarios, their CEOs end up in prison &/or with a criminal record. Having regular checks done on equipment also saves injuries & lives. You’d be surprised how many people would use faulty equipment just to get a job done, regardless of whether it would injure or kill them. People’s knowledge of the equipment they use is also often lacking &, supplying training for use of equipment is also another opportunity to provide a service that benefits.

[sam_sam_sam]

PAT is a requirement under Electricity at Work Regulations, although this is an implied requirement rather than specified. If you have employees that get killed/seriously injured by faulty equipment & you don't have all the necessary H&S in place, you're going to jail. Employees need to be trained on a piece of equipment before they can use it. This involves checking the equipment for faults prior & post use, reporting systems for faults/suspected faults, regular maintenance & checks by a qualified person. It's only criminal not to have done it if there's an accident involving faulty equipment. Lots of insurance companies require PAT as part of their policies. Government & agencies are sticklers for it, many requiring that a valid PAT be produced before use of the equipment is permitted on their sites with many larger businesses following suit.

It's a huge industry with potential to expand &, although around 95% of failures can be found visually inspecting equipment, each failure also brings additional business in the way of fixing &/or procurement.

PAT is undertaken on site by us, but the failures are removed back to our workshop for analysis & reporting back to our clients. Testing & repairs in our workshop sometimes require the appliance be live &, given the items are faulty, likely to trip MCBs/RCDs, etc.. Live & under a thermal camera is the quickest way I've found to identify shorts. The independent H&S consultants we use will allow faulty equipment to be made live, but only if it's via an isolation transformer, with PPE & under strict conditions. We have to be in compliance with the H&S to achieve ISO status needed to maintain the contract.

For the amount of work that failure repairs produces at the moment, it's not worth spending £5k+ on a custom transformer station.

As for experience, I've almost 20 years experience in electrical & PAT, qualified as an electrician to C&G Design & Verification. Person's undertaking PAT are required to be suitably qualified &, although a monkey with some stickers could do a test, if the equipment were faulty & someone was injured, there'd be a lot of uncomfortable questions to answer that would almost certainly end with a minimum of a fine & possible criminal conviction.

Dismissing PAT… it's highly profitable with little in the way of overheads. The work is easy & clients are professional. Businesses not doing it are liable to damages & in worst case scenarios, their CEOs end up in prison &/or with a criminal record. Having regular checks done on equipment also saves injuries & lives. You'd be surprised how many people would use faulty equipment just to get a job done, regardless of whether it would injure or kill them. People's knowledge of the equipment they use is also often lacking &, supplying training for use of equipment is also another opportunity to provide a service that benefits.

How often do eco get prosecuted for there negligence of the standards that you have outlined above because in this country they have standards but rarely enforce and when is enforced they are just doing to set an example to detour someone else from doing the same thing