Recent content by ericmark

I have a big problem with LED lights because manufacturers don't seem to use the wording one expects to describe their products. An LED is a current dependent device and DC but often the driver required to limit the current be it a simple resistor or a switched mode device is built into the...

I got caught out using a phase rotation meter. Easy job fit a socket made sure rotation was correct. However rest of factory was wrong. In the main only need for meter is when connecting two generators together I no longer carry it. Not been used for years.

It is surprising what does not pass finger test from consumer units where you can flick out blanks with your fingers to PLC's which were designed to be mounted inside a panel. I got in a lot of trouble for pointing this out in Uni. There was it seems a standard question paper which was given...

Got an email asking why I don't use this site anymore did not remember using it. However used old email address, and common password, and all worked so clearly I have used this in the past. Forced to retire due to industrial injury but still take an interest from time to time do odd days pat...

I no longer work so just interested on how things have progressed. Around 2000 I had to do a lot of PAT testing and thought it would be good to store results on the PC. However I was some what disapointed with software. Whole idea is it would flag up trends where items were starting to for...

Yes I would agree the time scale reflects use. It seems from the HSE publications as the tester it's not up to me to fix the time but up to the manager. And I suppose if the manager has passed the exam that's correct. However in the main their name may be on the paperwork but they rely on us the...

I have seen a few comments by HSE that we are going OTT with PAT testing and 12 months tickets on all items and testing new items is not required. Considering we are only really interested in safety I do sometimes wonder why we do so many tests? Does it really matter if it draws 1kW, 2kW or...

I would consider using biggest MCB but there are a few points. With RCD this no longer applies and in a bathroom 12 volt is maximum voltage not 50 so should it not be: R = 12v / Ia ? I can't find formula under 701 in 17th and both 12 and 24 volt AC are given according to zone. Idea is of...

Careful with Induction hobs because of "Boost" most have no diversity.

I wonder what you are using to measure with? In UK we often use the earth loop impedance tester but that is where the suppliers earth is 21 ohms or less. Where supplied by non UK suppliers then they may not follow the rules we have in UK. So you may need to use a bridge to measure resistance of...

I thought so long as you use something like Ali-tube to BS 8436 Guardian, Earthshield, Flexishield, or Afumex cable the only place where you need RCD protection on lights is the bathroom? Why anyone would use twin and earth I don't know hard to seal as flat cable and if any of the cable is...

It would depend who you worked for. I worked for GEC and was told in no uncertain terms to take all my tools home the company were only insured for tools they provided. Also they were responsible to do all calibration so not allowed any meters that were not calibrated. So I would turn up with...

With IT equipment often the earth is connected through the printed circuit and 25A can damage the printed circuit which could lift and latter break. This is why we use the low current test. Where one knows there are no printed circuits then 25A is no problem.

I will give an example where I have used it. Site with loads of 110 volt cables mainly 1.5mm

I tried to get a lock device for main Siemens Moulded breaker 300A. Seems they will only fit when horizontal in multi-breaker panel and in single unit panel they would not fit. Had to get hasp and staple welded to face plate shame as all the nice paint was destroyed. It seems locking off is not...