Cord work - Page 1
Forum section: electronics / beginners

author: fixit7
author_rank: Regular Contributor
timestamp: July 01, 2019, 05:14:10 pm
content: It's hard to remember to put shrink tubing on first.It may not be very clear, but there is a piece of shrink tubing that is ready to slide down and shrunk.The plan is the use Gardner Bender Liguid tape, 3 coats, then slide the shrink tubing in place and shrink it.And also 3 coats over a 4 inch section of the cord where the repairs were made.What do you think?

author: Shock
author_rank: Super Contributor
timestamp: July 01, 2019, 06:34:18 pm
content: If it's mains cable don't splice it, replace it. Your splices look really long. Unless length is an issue stagger linesman splices so there is never a possibility of shorting and individually shrink them. The advantage of these splices is they hold up to mechanical strength as well. Then use adhesive lined shrink.

author: fixit7
author_rank: Regular Contributor
timestamp: July 01, 2019, 07:00:29 pm
content: Okay.I noticed the ground wire is attached to the grinder itself.Isn't that supposed to go to the ground on the cable? :-)If a hot wire were to come loose and touch the metal grinder, then I would be eltro******.Andy

author: Gyro
author_rank: Super Contributor
timestamp: July 01, 2019, 08:30:17 pm
content: Quote from: fixit7 on July 01, 2019, 07:00:29 pmYou're making no sense. "the ground wire is attached to the grinder itself", ok fine.QuoteWhat, the grinder? You just said it was. If not, what's the "that"?

author: sokoloff
author_rank: Super Contributor
timestamp: July 01, 2019, 08:53:06 pm
content: Quote from: fixit7 on July 01, 2019, 07:00:29 pmWell, if a hot wire came loose and touched the metal grinder which is also connected to the ground, you'll blow the breaker from the dead short from line to ground.

author: fixit7
author_rank: Regular Contributor
timestamp: July 01, 2019, 09:54:07 pm
content: Quote from: Gyro on July 01, 2019, 08:30:17 pm"That" is the green wire that was connected to the grinder.The green wire in the cord serves what purpose?(I know the answer.)

author: Gyro
author_rank: Super Contributor
timestamp: July 01, 2019, 10:02:24 pm
content: So you already said that the ground (green) wire is connected to the grinderand"isn't that supposed to go to the ground on the cable"butyou already said that it is. See my point?

author: Brumby
author_rank: Unknown
timestamp: July 01, 2019, 11:40:12 pm
content: @fixit7 The fact that you are asking questions like these, makes me rather concerned that you are working on mains cabling. I knew exactly what went whereand whybefore I first even touched mains cabling.Quote from: Shock on July 01, 2019, 06:34:18 pmIf it's a flex cable, then replacement is the ONLY safe option. If it's a fixed cable (inside conduit or secured to an immovable object, like a wall) then splicing is an option.QuotePlease, please, please do this!!!!! It's one extra step to reduce the risk should one of your splices become exposed.

author: Monkeh
author_rank: Super Contributor
timestamp: July 02, 2019, 12:39:44 am
content: Quote from: fixit7 on July 01, 2019, 09:54:07 pmSo if the green wire in the cord isn't the green wire connected to the grinder, what the hell is the green wire connected to the grinder?

author: ptricks
author_rank: Frequent Contributor
timestamp: July 02, 2019, 12:48:22 am
content: replace it, the cost of a new cord is about $5. Even an old ATX power supply cord will work.

author: fixit7
author_rank: Regular Contributor
timestamp: July 02, 2019, 12:59:50 am
content: Quote from: ptricks on July 02, 2019, 12:48:22 amI already have a replacement cord.I made another separate post to make sure I hook it up right.

author: fixit7
author_rank: Regular Contributor
timestamp: July 02, 2019, 01:09:16 am
content: Quote from: Monkeh on July 02, 2019, 12:39:44 amI agree, my friend, that the green wire asoriginallyinstalled, served no purpose.The hot wire and neutral were securely fastened.I made a separate post showing the loose wires going to the motor, and where the green wire from the OLD cord was fastened to the grinder.So I could get advice on how to connect the new cord correctly.I can not find that post?Hmmmm...

author: Monkeh
author_rank: Super Contributor
timestamp: July 02, 2019, 01:59:22 am
content: Quote from: fixit7 on July 02, 2019, 01:09:16 amWhat was the green wire originally installed and where did it go?!Your posts are lacking entirely in context. We are not mind readers.

author: sleemanj
author_rank: Super Contributor
timestamp: July 02, 2019, 02:04:49 am
content: You seem to have poor understanding of what the earth wire is for. You really shouldn't be playing with this stuff.But anyway, in simple terms, the sole and entire purpose of the green wire is to connect the Earth pin of your power socket to any exposed metal part you can touch on the tool.Your other thread seems to show that is exactly what it was and should be doing.

author: MarkF
author_rank: Super Contributor
timestamp: July 02, 2019, 02:07:35 am
content: It would have really been helpful if the grinder cord replacement was all ONE thread.Here are the other two threads for reference:https://www.eevblog.com/forum/beginners/update-grinder-switch/https://www.eevblog.com/forum/beginners/record-a-bench-grinder/Replacement switch:(SPST) - ¾ HP 125-250 VAChttps://www.amazon.com/Gardner-Bender-GSW-110-Electrical-Terminal/dp/B00004WLK6/ref=sr_1_36?keywords=10+amp+ac+switch&qid=1561947300&s=gateway&sr=8-36Plus images:

author: Jwillis
author_rank: Super Contributor
timestamp: July 02, 2019, 02:57:28 am
content: The green wire or Earth ground is there for safety. IF there is a failure in the motor that causes a short to the metal body , the green wire transfers that electrical charge directly to earth ground instead of though you.Connect the green wire to the metal body of the grinder or body of the motor.

author: fixit7
author_rank: Regular Contributor
timestamp: July 02, 2019, 03:10:22 am
content: Quote from: Jwillis on July 02, 2019, 02:57:28 amOk.

author: fixit7
author_rank: Regular Contributor
timestamp: July 02, 2019, 06:01:36 am
content: Thanks. Your artwork is truly impressive. :-)Would a single pole Leviton 15 amp switch be an acceptable substitute?It fits the hole the best and I can frame it with some 1/8th inch plywood to fill the gap.

author: sokoloff
author_rank: Super Contributor
timestamp: July 02, 2019, 10:32:31 am
content: If the factory original switch functions, why "improve" upon it?It was designed for the purpose and has the physical "mash it blindly to turn off the grinder in the event of emergency" benefit.

author: Ysjoelfir
author_rank: Frequent Contributor
timestamp: July 02, 2019, 01:17:41 pm
content: Quote from: sokoloff on July 02, 2019, 10:32:31 amI mentioned that in the switch replacement thread, too, but fixit7 seems to absolutely want to replace that nice beefy switch for whatever reason.

author: MarkF
author_rank: Super Contributor
timestamp: July 02, 2019, 03:18:55 pm
content: Quote from: fixit7 on July 02, 2019, 06:01:36 amMy grinder has a toggle switch like the one you linked to and like I used in the picture.I don't see a problem using a Leviton switch (But, I would not use a cheap one).A round toggle switch would be easier to mount.Instead of plywood, get a plastic (or metal) electrical box cover and trace over your original cover.Paint to suit.https://www.lowes.com/pd/CARLON-2-Gang-Square-Plastic-Electrical-Box-Cover/3129415I would try to find a piece of plastic or metal. I would not use wood.

author: fixit7
author_rank: Regular Contributor
timestamp: July 02, 2019, 05:08:00 pm
content: Thanks MarkF.Great idea.I will get the cover like your link.I can drill holes to match those on the grinder.I will try to make it look nice.

author: fixit7
author_rank: Regular Contributor
timestamp: July 02, 2019, 05:12:50 pm
content: Quote from: sokoloff on July 02, 2019, 10:32:31 amI am not trying to improve on it.I want a suitable replacement, and if possible use what I already have.I have a wattometer. I plan on seeing how much is draws in startup.

author: MarkF
author_rank: Super Contributor
timestamp: July 02, 2019, 08:24:48 pm
content: This would be a good replacement cord if you don't have one:https://www.amazon.com/Conductor-3-Prong-Wiring-Replacement-Pigtail/dp/B07MCBPG5V/ref=pd_cp_23_1?pd_rd_w=51HB3&pf_rd_p=ef4dc990-a9ca-4945-ae0b-f8d549198ed6&pf_rd_r=J0GJQJV3ZTX7K25A2C68&pd_rd_r=8eecd1ac-9d06-11e9-8864-c1ee86d5769a&pd_rd_wg=02759&pd_rd_i=B07MCBPG5V&psc=1&refRID=J0GJQJV3ZTX7K25A2C68Otherwise you could buy a short extension cord with 3 prongs and 14/3 AWG wire (three 14 gauge wires). Then cut it to length for the grinder.Sometimes cutting an extension cord in the middle and only using half is cheaper and easier to find.Depending on the grinder placement in your shop, you may want a long cord.In order to secure the cord, a plastic cable tie just inside the grinder cord hole will keep it from being pulled out.https://www.amazon.com/HS-Plastic-Fencing-Outdoor-Purpose/dp/B078NQBSJR/ref=sr_1_19?keywords=cable%2Btie&qid=1562100911&s=gateway&sr=8-19&th=1

author: fixit7
author_rank: Regular Contributor
timestamp: July 03, 2019, 01:24:07 am
content: Quote from: sleemanj on July 02, 2019, 02:04:49 amI do not agree with your opinion that "I should not be playing with this stuff."I had my grinder repaired at least 15 years ago.When the original switch failed, I ran the wiring to a Leviton light switch rated for 15 amps.I simply got to the point where I wanted it to look neater.Have a good week.

author: Brumby
author_rank: Unknown
timestamp: July 03, 2019, 04:14:49 am
content: Quote from: fixit7 on July 03, 2019, 01:24:07 amYou may not agree, but you should understandwhysuch comments are being made. Specifically, the questions you asked around the earth wire clearly show you do not understand how an earthing system works. The concept is simple and it has major safety implications - especially in a workshop environment.This will be a concern to pretty much anyone on this forum who has done anything involving mains power and is the reason for such comments being made.It is good that you have brought questions here and that we can offer some assistance - but unless you have someone standing next to you as you work, there can be no certainty as to how well you understand what's been said. We certainly can't provide the tuition necessary to ensure thorough training. The fact that you may have added a switch is no guarantee you were doing things properly. We simply don't know how well you did that job. Applying some common sense may have allowed you to get away with that, however there may be some things you should have done to improve the safety and/or reliability. Just because it hasn't blown up or killed anyone - so far - doesn't mean you did a good job.What I will say is this: If you were to sell this unit to anyone here, the first thing we would do is open it up and check the wiring.These comments of mine and others are not meant as a "put-down". They are meant to alert you to the fact that there is a concern for your safety due to a lack of understanding. If you wish to take offense with what I've said above, then that is your prerogative, but there will be many members here who will be nodding in agreement, even if they do not post.

author: Mechatrommer
author_rank: Super Contributor
timestamp: July 03, 2019, 06:37:28 pm
content: isnt bench grinder (any mains ac motor) suppose to have 3 wires out from the motor? and to a capacitor?or does it have a built-in capacitor inside the motor cover designed for eternal life? btw i dont like that metal toggle switch handle. if something wrong (in case the OP doesnt want to connect earth wire to chassis), that metal handle will be a good 110-220V conductor from chassis to human body. i prefer plastic/insulated handle, ymmv.

author: fixit7
author_rank: Regular Contributor
timestamp: July 04, 2019, 12:28:25 am
content: Quote from: MarkF on July 02, 2019, 08:24:48 pmI ended up using 2 cable ties to keep the cable from being pulled out.Thanks for not assuming the worst when I ask questions.It's a big way I learn.Andy

author: ptricks
author_rank: Frequent Contributor
timestamp: July 05, 2019, 01:35:18 pm
content: Quote from: Mechatrommer on July 03, 2019, 06:37:28 pmDepends on the motor , cheaper grinders can probably get away with a shaded pole motor , like the ones on fans that don't require a start capacitor.

author: fixit7
author_rank: Regular Contributor
timestamp: July 07, 2019, 09:37:59 pm
content: My grinder has no capacitor.But it is 34 years old.It is very heavy.4 amp motorI think it is just a big motor and doesn't really need a capacitor.It must be well made to have lasted this long.