16 Amp Plug & Socket.....How Tight?

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Distinterior

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I was using my Hammer A3 31 planer thicknesser quite a bit over the weekend ( hadnt used it for about 5 weeks) and decided to change to new knives.
Over the two days, I ended up plugging in and unplugging the 16amp plug a few times and it struck me as being far more difficult to do than I remember in the past.

Do these plug & sockets tighten up over time? If so, is there anything I can do to make insertion & removal easier...?.....or am I just getting weak in my old age...?
 
A lot of my power tools are 110 v . The plugs/ sockets are imo almost identical to 16 volt sockets/pluga plugs it’s not uncommon to have to give them a firm pull to engage/disengage . Can’t see why a little dab of silicone grease or petroleum jelly would do any harm ..happy to be corrected though..
 
I was using my Hammer A3 31 planer thicknesser quite a bit over the weekend ( hadnt used it for about 5 weeks) and decided to change to new knives.
Over the two days, I ended up plugging in and unplugging the 16amp plug a few times and it struck me as being far more difficult to do than I remember in the past.

Do these plug & sockets tighten up over time? If so, is there anything I can do to make insertion & removal easier...?.....or am I just getting weak in my old age...?
You've answered your own question, grandad, and I share your pain!
 
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or am I just getting weak in my old age...?
That is probably the reason, the same as why a 20Kg bag of cement feels a lot heavier than it once did. The better solution would be a 16 amp socket with isolator and in a one man workshop you are in total charge of the isolation. The other way would be to turn off your 16 amp supply at the main board rather than un plug it when changing the knives and if you do not have line of sight to that board then use a lockout device so it cannot be turned back on.
 
I have never thought of lubricating an electrical contact, if the lubricant created a film then that would be resistive and could cause overheating of the contact. Having worked before cordless became dominant then I am used to the 110 volt sockets whch are the same as a 16 amp one except the color and locating tab but they have always been tight and required a tug which is the same as my 16 amp plug on the P/T which is also tight but that has an isolator switch.
 
Many years ago I did some work with a team that did a lot of outdoor stuff, and it was common for them to have packed their 3 pin plugs with glazier putty (in an effort?) to make them waterproof...
Nothing to do with the OP's original question, of course - but I've a feeling they used to smear the same on the actual pins as well...
 
Red, blue, yellow...
16A, 32A.
Interlocked switched sockets will stop the plug pulling out by accident and let you isolate without having to unplug.
£30 typically. Ebay is your friend.
 

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In theory the tighter the plug the better the connection between plug pin and socket receptacle unless there is dirt fouling the plastic plug body and socket
 
I had a similar issue with a plug and socket - essentially down to cheap rubbish with poor tolerances between the male and female parts. So bad that there was a danger of pulling the socket off the wall.
As suggested, careful application of lubricant may help, or exchange for better quality. Note that some lubricants may cause some plastics to swell; best to avoid petro- chemical products.
Being cheapskate, I sanded down the male plastic part on the plug until it was a better fit. It is not loose and, in any case, the safety catch on the lid is still in place so there are no safety implications.
The electrical pins and sockets were not touched.
Duncan
 
110v plugs on building site's have a hard life, it was common for them to be sanded to remove digs and raised bits to enable easier fitting into the socket of a multiway distribution box or transformer. The operative dragging the box across the floor was also common when the cable was just that bit too short.
 
Thanks for the comments & suggestions.

I have a number of 16a sockets dotted around my workshop, all of which were purchased at Screwfix about 2 years ago, mainly for possible future use, but only 2 are used regularly.
I tried the P/T plug in a couple of the other sockets and it was straightforward to insert & remove.
I dont have any separate isolators on individual 16a sockets, just relying on the on/off buttons on the individual machines.

I suppose this particular socket has had the most use as it is where the P/T lives 99% of the time and I always remove the plug every time I have finished using it for the day.
I always make certain to unplug everything in the workshop when I'm finished for the day.......I never even leave batteries charging overnight.....!

Perhaps I'll just try a quick squirt of dry PTFE spray and see if that improves things?

Edit.
I'm pretty certain that it's the 3 pins that are tight, not the plastic shrouds on the plug & socket.....
 
There are proprietary electrical contact cleaners and lubricants that will be safe.
As @Spectric says, don't squirt any old random stuff in there because you don't want to introduce a resistance, not do you want to put in something electrically conductive.
 
I've generally found 16amp tolerances can be a part in many plug/socket matings... Cheapies are likely the worst... And if you have say a good quality socket and a cheapie plug...? Similarly if the other way around...? As regards lubricating ... not something I'd go for; though others may agree (based on their experience).

Ideally a local isolator for the socket - even better "all" sockets would be far easier, safe, and more convenient; though I would still disconnect (remove) the item from the socket even with an isolator invoked. Using the 16amp blue/round pin interlocked system is fine if you're happy with them; bearing mind that it means you have to have enuff of them installed for your use/convenience ? And extension reels for them exist of course but ain't cheap.
 
Graphite is both a good lubricant and a good electrical conductor, so should be ideal for your situation. Rub the pins with the lead of the softest pencil you have - 6B or softer.
 
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Many years ago I did some work with a team that did a lot of outdoor stuff, and it was common for them to have packed their 3 pin plugs with glazier putty (in an effort?) to make them waterproof...
Nothing to do with the OP's original question, of course - but I've a feeling they used to smear the same on the actual pins as well...
They would have been better filling the insides with hot melt glue and sticking the top back on too, different situation but essentially how I waterproofed connections on outdoor Xmas lights when I used to do them.
Ian
 
A lot of my power tools are 110 v . The plugs/ sockets are imo almost identical to 16 volt sockets/pluga plugs it’s not uncommon to have to give them a firm pull to engage/disengage . Can’t see why a little dab of silicone grease or petroleum jelly would do any harm ..happy to be corrected though..
110v are yellow - 240v 16a blue or 240v black - 3-phase? red /?
I've always used petroleum jelly on contacts that are likely to get exposure to damp conditions, especially 12v car battery termenals.
 
110v are yellow - 240v 16a blue or 240v black - 3-phase? red /?
I've always used petroleum jelly on contacts that are likely to get exposure to damp conditions, especially 12v car battery termenals.
This is interesting-a mechanic friend of mine used to smear some type of grease onto the battery terminals on the trucks he worked on I assumed it was to stop the nut seizing. I also came across this yesterday which sounds like it might work for the op
 

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