Electrical testing on Machines

[Tonkolili]

The company i work for manufactures machinery which have a control panel that houses all of the switchgear,inverters starters, PLCs etc, we carry out the electrical install on the machine but when it goes to the client, we are not responsible for the mains supply to the control panel, what i want to know is what are the regulations on testing the Earth Loop impedance etc on production lines. My opinion is that when we install the machine (when i say machine its actually a production line) we should carry out a full electrical test and inspection as you would on any installation, most of the circuits are Motors,Lighting,safety circuits and instrumentation. I have encountered this before where no testing is sort by the client or anybody when installing machinery, it seems to be the opinion that it is just the fixed wiring of a building that requires testing ??? any comments would be appreciated

 

[Farmelectrics]

why dont you ask for an eic on the supply cable to your machine

 

[Farmelectrics]

every electrical circut will have or should have an electrical test cert have you asked for them,. why would you want them if your just supplying the machine

 

[davesparks]

He's asking if they should certify the circuits that they install when they install the machine

 

[Farmelectrics]

well then the answers yes

 

[Darkwood]

Whoever installs the supply will cert' it for compliance, whoever installs the machine only need to clarify before energising that everything is sound and Zs is good of the supply as is the duty of anyone energising a new install, although I'd recommend there be a section in the commisioning paperwork to confirm its been checked and passed.

The machine supply is classed as part of the fixed wiring of the building so like all circuits it requires testing, the equipotential bonding and earthing of the building also requires confirming.

 

[Knobhead]

And here in lies a problem, advice given by domestic electricians regarding industrial matters.

 

[LeeH]

Are you asking if you can apply 7671 after the isolator on your 'machine' exactly like you do on the fixed wiring?

If so the answer is no, it's not possible to calculate or measure the EFL through the DC bus on a VFD. The manufacture will guarantee a disconnection time under fault. Ask them.

Circuits that are DOL can be as you can get the tripping curves for motor overloads from the manufacture such as Telemec/Schneider overloads.

Cable CCC's and installation methods can also be lifted from 7671 but 60204 needs to be your main focus.

 

[LeeH]

I'm sure Tony and others can add much more.

 

[Knobhead]

I know I wouldn’t like to get the machine going after someone had tried testing to BS7671 compliance. Testing the supply is about it.