Will Vibration cause a motor contactor to drop out? - Page 2 - Electrician Talk - Professional Electrical Contractors Forum
CLICK HERE AND JOIN OUR COMMUNITY TODAY, IT'S FREE!
Go Back   Electrician Talk - Professional Electrical Contractors Forum > Electrical Trade Topics > PLCs, VFDs, Motors and Controls


Like Tree40Likes
Reply
 
Thread Tools Display Modes
Old 12-18-2018, 03:58 PM   #21
Senior Member
 
just the cowboy's Avatar
 
Join Date: Sep 2013
Location: Colorado
Posts: 1,630
Rewards Points: 6
Default Fast acting at little over half the coil current

Quote:
Originally Posted by gpop View Post
I think you have a valid point splatz. I would have to bench test to see what the fuse is carrying. I know it works as i have used it in the past just never thought of the physics behind it.
It should be a fast acting fuse at just over half the coil current. Just the differance between the element resistance and the contacts resistance will cause most of the current to flow thru the path of least resistance the contacts.
@gpop didn't know others new this one.
splatz and benwinch07 like this.
__________________
A cowboy may get thrown down, but he always gets up and walks forward and don't look back at what thru him.
just the cowboy is online now   Reply With Quote
Join Contractor Talk

Join the #1 Electrician Forum Today - It's Totally Free!

ElectricianTalk.com - Are you a Professional Electrical Contractor? If so we invite you to join our community and see what it has to offer. Our site is specifically designed for you and it's the leading place for electricians to meet online. No homeowners asking DIY questions. Just fellow tradesmen who enjoy talking about their business, their trade, and anything else that comes up. No matter what your specialty is you'll find that ElectricianTalk.com is a great community to join. Best of all it's totally free!

Join ElectricianTalk.com - Click Here JOIN FOR FREE


Warning: The topics covered on this site include activities in which there exists the potential for serious injury or death. ElectricianTalk.com DOES NOT guarantee the accuracy or completeness of any information contained on this site. Always use proper safety precaution and reference reliable outside sources before attempting any construction or remodeling task!

Sponsored Links
Advertisement
 
Old 12-18-2018, 04:09 PM   #22
Senior Member
 
JRaef's Avatar
 
Join Date: Mar 2009
Location: SF Bay Area, California
Posts: 5,108
Rewards Points: 2,100
Default

I doubt it is the contactor or aux contacts, there are NEMA specifications for vibration that have to be met. I have put countless starters on the sides of rock crushers without problems.


What I HAVE seen on numerous occasions is Normally Closed push button contacts vibrating open. You say the starters are A-B, but are the buttons as well? I see people cheap out on the pilot devices because they assume that they are all the same, but that's just not true. ABB push buttons are notorious for that, but I've seen it on off-brand cheap stuff as well. I had to stop using ABB pilot devices on the crusher panels I built, I just couldn't get the E-Stop buttons to hold in. If it's fairly consistent, put a temporary jumper in around the Stop contacts and see if the problem goes away (make sure EVERYONE knows there is no E-Stop). If the problem goes away, replace then with another brand.
__________________
"If you don't know where you're going, then any direction will do." -- Lewis Carroll
JRaef is online now   Reply With Quote
The Following User Says Thank You to JRaef For This Useful Post:
benwinch07 (12-18-2018)
Old 12-18-2018, 06:02 PM   #23
Senior Member
 
Join Date: May 2018
Location: florida
Posts: 1,485
Rewards Points: 1,190
Default

Quote:
Originally Posted by just the cowboy View Post
It should be a fast acting fuse at just over half the coil current. Just the differance between the element resistance and the contacts resistance will cause most of the current to flow thru the path of least resistance the contacts.
@gpop didn't know others new this one.
Cut my teeth on relay logic where you play guess which relay opened first. Another trick is to make a self latching relay and i still use that one to prove that i lost power for a split second.
just the cowboy likes this.
gpop is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 12-18-2018, 10:30 PM   #24
Junior Member
 
Join Date: Dec 2018
Location: Richmond, IN
Posts: 8
Rewards Points: 12
Default

Quote:
Originally Posted by splatz View Post
When it's rocking and rolling hard enough to shake the control cabinet, is the grinder hood moving enough to open that switch,
Winner Winner chicken dinner!

Thank you all for your awesome input! Some really great ideas and methods!

Since our Safety coordinator will rip us a new one for troubleshooting while the machine is on (probably for good reason, big picture wise, but thats a whole other rabbit hole in itself), The safety switch always had continuity while the machine was down and not shaking. I just happened to notice that some of the big ol' wingnuts that flip up and tighten down on the hood weren't all the way tight. I tightened them down and its been good ever since.

Sometimes I miss the simplest things
The operator cleans the thing out and reassembles it so theyre supposed to tighten it down. Usually if they dont tighten it enough it wont even turn on.

I love the fuse idea! If Im understanding it right, you would use the fuse to jumper across the contacts, sharing the load going through the button? And if the contacts open up, the whole load will go through the fuse and blow? Thats ingenious.

As far as telling the operator to not overload the grinder...They "only throw two or three sheets in at a time" so my efforts are better spent in other areas, lol.

We do primarily buy AB switches and buttons. Sometimes Schneider. Good to know about ABB though, I'll keep that in mind.

Thanks again, guys, I loved hearing from you!
Cheers!
micromind, splatz, MikeFL and 1 others like this.
benwinch07 is offline   Reply With Quote
Old 12-19-2018, 12:03 AM   #25
Senior Member
 
Switched's Avatar
 
Join Date: Dec 2012
Location: California
Posts: 6,114
Rewards Points: 8,956
Default

@benwinch07, thanks for posting the fix! I like these threads about stuff I never work on, especially when I get to hear about what the actual issue ended up being.
splatz, MikeFL and gpop like this.
Switched is online now   Reply With Quote
Old 12-19-2018, 05:02 AM   #26
Senior Member
 
460 Delta's Avatar
 
Join Date: May 2018
Location: Southern Ohio
Posts: 799
Rewards Points: 944
Default

Thank you for taking the time to tell us what the problem was and the repair worked out to be, it helps us to all be better electricians. I try to file away info from this stuff and modify it to help in my day to day work.
splatz likes this.
__________________
Perfection is the enemy of good enough
460 Delta is offline   Reply With Quote
Old 12-19-2018, 05:03 AM   #27
Senior Member
 
MikeFL's Avatar
 
Join Date: Apr 2016
Location: The Sunshine State
Posts: 5,449
Rewards Points: 2,994
Default

Ditto on letting us (and anyone who encounters the thread) know the outcome. It's rare all too often.
Glad it worked out for you.
splatz likes this.
__________________
Michael Gookin, President
GPS Timers

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

(833) GPS-TIME
MikeFL is online now   Reply With Quote
Old 12-19-2018, 05:13 AM   #28
Hackenschmidt
 
splatz's Avatar
 
Join Date: May 2015
Location: Parts Unknown
Posts: 8,499
Rewards Points: 4,396
Default

Thanks for the follow up, plus for a question that got @460 Delta to bring out one a real good one from his bag of tricks, I am going to be experimenting with that one in the Laboratory (basement).

Quote:
Originally Posted by benwinch07 View Post
Winner Winner chicken dinner!

Since our Safety coordinator will rip us a new one for troubleshooting while the machine is on (probably for good reason, big picture wise, but thats a whole other rabbit hole in itself), The safety switch always had continuity while the machine was down and not shaking. I just happened to notice that some of the big ol' wingnuts that flip up and tighten down on the hood weren't all the way tight. I tightened them down and its been good ever since.

I love the fuse idea! If Im understanding it right, you would use the fuse to jumper across the contacts, sharing the load going through the button? And if the contacts open up, the whole load will go through the fuse and blow? Thats ingenious.
__________________
Everything Should Be Made as Simple as Possible, But Not Simpler
splatz is offline   Reply With Quote
Old 12-19-2018, 06:15 AM   #29
Senior Member
 
Join Date: May 2018
Location: florida
Posts: 1,485
Rewards Points: 1,190
Default

Quote:
Originally Posted by benwinch07 View Post
Winner Winner chicken dinner!

Thank you all for your awesome input! Some really great ideas and methods!

Since our Safety coordinator will rip us a new one for troubleshooting while the machine is on (probably for good reason, big picture wise, but thats a whole other rabbit hole in itself), The safety switch always had continuity while the machine was down and not shaking. I just happened to notice that some of the big ol' wingnuts that flip up and tighten down on the hood weren't all the way tight. I tightened them down and its been good ever since.

Sometimes I miss the simplest things
The operator cleans the thing out and reassembles it so theyre supposed to tighten it down. Usually if they dont tighten it enough it wont even turn on.

I love the fuse idea! If Im understanding it right, you would use the fuse to jumper across the contacts, sharing the load going through the button? And if the contacts open up, the whole load will go through the fuse and blow? Thats ingenious.

As far as telling the operator to not overload the grinder...They "only throw two or three sheets in at a time" so my efforts are better spent in other areas, lol.

We do primarily buy AB switches and buttons. Sometimes Schneider. Good to know about ABB though, I'll keep that in mind.

Thanks again, guys, I loved hearing from you!
Cheers!
When you get bored take a look at the safety switch and see if you can make a self latching relay (just about the same setup as a hard wired start/stop starter set up except you are latching a relay rather than a contractor). Hook a indicating lamp and a reset button on the outside of the panel for the operator.

Then any time the machine shuts down due to the door switch the light will come on and stay on indicating that was the problem. Keeps safety happy as you do not need to open the door, keeps you happy as the operator doesn't need to disturb you tea breaks.
splatz and MikeFL like this.
gpop is offline   Reply With Quote
Old 12-19-2018, 07:35 AM   #30
Senior Member
 
MikeFL's Avatar
 
Join Date: Apr 2016
Location: The Sunshine State
Posts: 5,449
Rewards Points: 2,994
Default

Quote:
Originally Posted by gpop View Post
When you get bored take a look at the safety switch and see if you can make a self latching relay (just about the same setup as a hard wired start/stop starter set up except you are latching a relay rather than a contractor). Hook a indicating lamp and a reset button on the outside of the panel for the operator.

Then any time the machine shuts down due to the door switch the light will come on and stay on indicating that was the problem. Keeps safety happy as you do not need to open the door, keeps you happy as the operator doesn't need to disturb your tea breaks.
I was in a very nice restaurant for lunch a few years ago, up north, and when the waitress asked what I want to drink I said I'll have a spot of tea (meaning a cup of hot water & a tea bag with sides of sugar & cream). She was quite dramatic. "What the hell is a spot of tea?..."

@gpop is a transplanted Brit living in our beautiful state of Florida. You can catch those subtle nuances in his posts. He brings a considerable wealth of knowledge to the forums.
__________________
Michael Gookin, President
GPS Timers

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

(833) GPS-TIME
MikeFL is online now   Reply With Quote
Old 12-19-2018, 08:09 AM   #31
Senior Member
 
just the cowboy's Avatar
 
Join Date: Sep 2013
Location: Colorado
Posts: 1,630
Rewards Points: 6
Default

Quote:
Originally Posted by gpop View Post
Cut my teeth on relay logic where you play guess which relay opened first. Another trick is to make a self latching relay and i still use that one to prove that i lost power for a split second.
Me too before PLC's, like me I guess you did tube drives for varable speed motors.

I am doing the latching trick right now with a small PLC for troubleshooting a relay logic problem.
Nice to see the old skills still at work.

Cowboy
splatz and MikeFL like this.
__________________
A cowboy may get thrown down, but he always gets up and walks forward and don't look back at what thru him.
just the cowboy is online now   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Bus drop cable WPNortheast General Electrical Discussion 3 12-14-2017 06:12 AM
Bus drop cable WPNortheast Residential Electrical Forum 3 12-11-2017 07:41 AM
Splices and voltage drop swimmer Residential Electrical Forum 17 12-19-2016 09:28 PM
is it OK to use the wire connector to connect the ground wire inside the drop ceiling mike883 General Electrical Discussion 29 07-20-2016 12:37 PM
Electric Company Service Drop Upgrade MustangRider6688 Services and Service Equipment 12 07-11-2016 05:03 PM


All times are GMT -4. The time now is 05:02 PM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.1
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Our Pro Sites Network
ContractorTalk.com | DrywallTalk.com | HVACSite.com | PaintTalk.com | PlumbingZone.com | RoofingTalk.com