Volt Stick Testers
Just some advice for the new or novice electrician, Voltage stick testers or pen testers are a handy addition to anyone’s arsenal of tools, but a few words of caution!
Please be aware these devices are a Non-Contact means of checking for voltages, they have their place & their purpose, but under no uncertain terms base or form your opinion that the circuit is indeed “DEAD” or not live based on this device alone.
They are prone to picking up stray voltages & often can give a false readings, especially if there are other cables close by or in the same cable run or tray work. Also if the internal battery fails then you will get no reading at all, indicating to you the user that no voltage is present!
They are however very handy for tracing cables, in trays or bunched together, to really get what this device has to offer will become apparent when trying to locate a single cable among many cables.
This will normally be a Two person operation as One can turn the supply on & off on the cable you are looking for and the second Person physically lifts the cables out of the bunch or tray looking for the supply to go on & off as per request. Two way radios or mobile phones are more often than not required the farther you get from each other, unless your both in shouting distance of course.
Correct method of proving a circuit
I do have a few different cheap volt sticks, and I only use for the purposes mentioned above, I have seen over the years a good many sparks (electricians) get electrocuted by placing trust in these devices, as a precaution here in the UK many companies forbid them on a work site or establishment as they are not an approved method for testing circuits. Like I said beforehand if you know what they can do & what they really cant then you can use them to your advantage.
The correct tool for the job is an approved voltage tester, and if legislation insists a proving unit to literally test the tester before & after use.
Again I have both of the above and again both Di-Log units, both have given me years of reliable service & didn’t break the bank.
If you want to be really specific and to the book, then the tester must be GS38 compliant, basically the test leads must be fused & only a pre defined amount of the probe is allowed to protrude from the insulation at the tip of the test probes, most have a removable end cap which allows more of the probe to protrude. To be honest mine got lost years ago and were the first things to be removed as I found them to be a hindrance.
If you are a beginner I would advocate leaving them in place as compliance people like to see them in place, as do inspectors from the main governing bodies.
A voltage tester will either tell you what voltage is present or indicate a voltage range you are in, both really tell you all you need to know, its either Live or Dead.
The proving unit simulates mains voltage allowing you to test your voltage tester before use to verify it is working correctly, once you have tested the circuit you are to be working on the tester should be tested again in the proving unit to check it is still working correctly.
All this may seem a little overboard, but when you receive your first electric shock & believe me you will, you will then realize the importance of good isolation methods. In a nutshell, it Bloody Hurts and consider yourself lucky that you lived to learn how to do it the safe way.
Plug top Testers
Again another good addition to the tool box, these are especially handy for a quick check on the condition of the circuit that is supplying the socket you have plugged it into.
There have been advancements over the last few years on additional functions these devices can perform, some can test RCD’s and Loop impedance values, personally for me this is left to the MFT (multi function tester) for me the only use I have for this is the buzzer, the rest I dont really look at.
I use this for finding which breaker or fuse is feeding a socket, simply put, plug it in, go to the fuse box or distribution board, hopefully its in ear shot, pull fuses or flick circuit breakers off until the buzzer stops, presto I’ve found my circuit.
If beyond hearing distance then I gotta walk and take a look & a listen, then a walk back, repeat.
As for any further testing I ALWAYS use the safe isolation procedure briefly talked about above before I do anything else. In industry there is also a locking device or devices applied to the supply end to ensure the circuit I make dead stays that way, some people have a bad habit of switching breakers back on if they see then off, applying a lock will save you from a nasty experience or possibly keep you off gods one way ticket to heaven list a little while longer.
If you are new to this or a DIY person, please remember this “if in doubt, dont !”
I have a team of engineers who work for me on an educational site, I always instill the above phrase into them on a regular basis, they are all very experienced, highly skilled & a well motivated bunch of lads, but we all have one thing in common, we all want to go home in the same condition we arrived in, well almost!
Please show the upmost respect when working with electricity, you cant see it, smell it, hear it but by god you can certainly feel it. (there are exceptions to some of the senses aforementioned)
I have had more than a few shocks over the years, mostly someone else’s fault and a few were my own, you can get complacent, pressured, hounded and the Friday feeling and lets not omit the Monday morning feeling, these will ALL bite you if you dont keep focused on what you are doing and sometimes more importantly what you are about to do.
If you are unsure, Stop, think, go for a cuppa get some trusted advice, think again, if still not sure or have doubt in your mind then Stop ! When you are sure and have no doubt in your mind then act. Always if possible undertake work when the supply has been isolated (Dead) then you wont be, dead that is.
I cant reiterate the importance of how dangerous electricity is, humans & electricity do not mix well and only a small electric current is required to literally stop your heart, less than 1/4 of an Amp is all thats required thats why RCBO’s & RCD’s are rated to trip above 30 milli-amps
I hope I have not put anyone off with the above, but hopefully made you the reader a little more aware of what we all take for granted daily, use daily and have all become so reliant on, this physical property we cant see, smell or touch
Stay safe until I add some more posts