petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- engineer
Does a padlock attachment on a din rail mounted CB constitute an acceptable disconnecting means for a group of small single phase motors fed from that CB?
padlock attachment on cb
- Thread starter petersonra
- Start date
- Status
- Location
- Wisconsin
- Occupation
- PE (Retired) - Power Systems
petersonra said:
Why do you ask? Do you think this would be any different than if the breaker was mounted into a panelboard?
petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- engineer
jim dungar said:
I see no difference.
Some one else is not so sure.
- Location
- Illinois
- Occupation
- retired electrician
Bob,
Who would be expected to use the disconnect? I would expect that you would have to open the panel and be exposed to energized parts to operate and apply the lock to the disconnect. That would require an electrically qualified person.
Don
Who would be expected to use the disconnect? I would expect that you would have to open the panel and be exposed to energized parts to operate and apply the lock to the disconnect. That would require an electrically qualified person.
Don
mdshunk
Senior Member
- Location
- Right here.
How about a lock on the JIC enclosure that's housing that DIN rail breaker?
davidr43229
Senior Member
- Location
- Columbus, Oh
Providing that:
1. is a UL489 rated breaker with a HP rating, Not a UL1077 Suplementary Breaker.
2. Is within sight of the motor
3. The person taging is out is "qualified person with Arc Flash PPE"
There are many reasons why you may want to shut off those small motors and keep the main panel running.
Once all the above is met then.....Yes Panduit & other manufacturers make a lock out, for them.
- Location
- Wisconsin
- Occupation
- PE (Retired) - Power Systems
davidr43229 said:
The person should also have voltage rated PPE. And provide appropriate placed barricades while the enclosure door is open.
Everyone please remember Electrical Safe Work Programs (NFPA 70E) involve a whole lot more than just arc flash protection.
davidr43229
Senior Member
- Location
- Columbus, Oh
Agreed Jim
Barriers, Voltage rated gloves and insulated tools. All are very important.
Barriers, Voltage rated gloves and insulated tools. All are very important.
petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- engineer
don_resqcapt19 said:
The end user is responsible for determining who is qualifed to use the disconnect.
That is a good point though.
petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- engineer
jim dungar said:
Arc flash protection on a 20A 120V circuit?
petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- engineer
davidr43229 said:
1. Is a Square D QOU breaker.
2. Within 5 feet or so.
3. Not up to me.
Keeping the panel live while locking out one or more motors is not a design criteria in this case.
davidr43229
Senior Member
- Location
- Columbus, Oh
Bob,
Yes
Anything over 50 volts. My "guess" would be voltage rated 00 gloves, untreated clothing of 4.5 oz and safety goggles with sideshields (level 0) and a barrier of 4-5" but usually most people use a standard default of 4', unless a Engineering Arc Flash calculation has been done.
Just my $.02
Yes
Anything over 50 volts. My "guess" would be voltage rated 00 gloves, untreated clothing of 4.5 oz and safety goggles with sideshields (level 0) and a barrier of 4-5" but usually most people use a standard default of 4', unless a Engineering Arc Flash calculation has been done.
Just my $.02
- Location
- Illinois
- Occupation
- retired electrician
Bob,
Don
I don't know what your application is, but in many cases the maching operator needs to be able to lock the equipment out to clear jams or other minor service work. This person would not normally be qualified to open the equipment and operate the disconnect.
Don
davidr43229
Senior Member
- Location
- Columbus, Oh
yes
50 volts & above.
50 volts & above.
- Location
- Wisconsin
- Occupation
- PE (Retired) - Power Systems
petersonra said:
I mentioned voltage PPE. NFPA70E is about all aspects of electrical safety, not just arc flash.
A qualified individual is one that is trained to perform that specific task. It is totally possible for a machine operator to be trained to open and perform a LOTO operation in a control panel but not be qualified for any other electrical task. Likewise, it is possible to be trained to make electrical terminations on de-energized equipment but not be qualified to perform a LOTO operation.
petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- engineer
don_resqcapt19 said:
Not an issue on this piece of equipment, but a good point.
davidr43229
Senior Member
- Location
- Columbus, Oh
Don,
Just my $.02
The origional thread here was can you use a CB as a disconnect, within the panel. The answer is yes and the "lock out" has to fit that CB.
Most companies that recognize the NFPA-70E are disallowing operators to preform this task, due to them not being qualified, certified or trained and have posted memo's to this effect. Tis a cultural change.
Just my $.02
petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- engineer
davidr43229 said:
Are you suggesting that companies are requiring that an electrician come lockout a machine to perform routine operator chores on it?
davidr43229
Senior Member
- Location
- Columbus, Oh
Define routine chores please?
- Status