what level of PPE would be required for TIE-BREAKER testing (all doors closed -just operating the test button for tie breaker) no arc flash stickers or calculations done on this switchgear. 2 incoming 13,2 lines, amp meters average 125 amps at 13,200v
PPE for tie-breaker testing 13,200v
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- Start date
zbang
Senior Member
- Location
- Roughly 5346 miles from Earls Court
Without any other info and under those circumstances, I think the best PPE will be a concrete wall.
Has it been tested in the past or is this a hot commissioning?
- Location
- Wisconsin
- Occupation
- PE (Retired) - Power Systems
When was the last time this breaker was closed?
Retired from a large hospital/research centers that had over a dozen 13.2 KV dual service substations with automatic tie breakers. One large research building we had 50 CAL PPE and 40 CAL for four other buildings. We had to wear that rated PPE to operate any buttons or switches except on two that had a remote operator approximately 20' away. On those we only had to wear the everyday 11 Cal rated PPE long sleeve shirt & pants. When we had to wear the 40 or 50 CAL PPE for transferring 13.2 or 4,16 KV switchgear is breakers had to have another qualified worker in the same PPE standing at least 10' away. Hope your company spends a little extra for 40 & 50 CAL hoods with a built in battery operating cooling fan. They are invaluable in a hot room. Work safe.
D. Castor
Member
- Location
- Port Angeles, Wash
- Occupation
- Electrical Engineer
If you are talking about closing this breaker to parallel two buses (and transformers), I'd be reluctant. It would be far preferable to find a way to close the breaker remotely. The load amps on the ammeter really don't have any bearing on the possible incident energy in the event of a short circuit (or out-of-phase closing).
If you're going to do it, wear the highest rated PPE you have along with high-voltage gloves. If this is a lineup of switchgear you are not familiar with, I probably wouldn't do it energized. I certainly would not ask anyone to do it.
If you're going to do it, wear the highest rated PPE you have along with high-voltage gloves. If this is a lineup of switchgear you are not familiar with, I probably wouldn't do it energized. I certainly would not ask anyone to do it.
The hospital that I retired from had both of two 13,200 volt dual service tie breaker designed for parallel operation so as not to produce a blip. ( had 4 separate services ) Even so we started the three 2 meg diesel gen sets & four 750 KW natural gas gen sets on line and either transferred power early in the morning or later at night. ( while no operations were going on ) Two other buildings had tie breakers that could be paralleled and the rest did not have that provision. Could never receive a ballpark figure how much extra parrellel 13,200 volt equipment cost. Was told it involves extra think they said bracing on wires & buss bars. Think it was set that parallel on primary side was set for a maximum of 4 seconds. Hopefully the NEC will require remote operators on all services over 480 volts. In one new office building we had a best in class remote transfer screen( Square D ) that also could display date & time of last 25 or so service outages, voltage fluctuations & tie breaker closures.
hillbilly1
Senior Member
- Location
- North Georgia mountains
- Occupation
- Owner/electrical contractor
I looked at some roll out energy management jobs for a large customer where 40 cal suits would be required. I took the project manger with me to look at one. With the hot electrical room, I told him there was no way our guys would wear it, so we declined to bid on them. Later I heard another contractor in I believe was Chicago, and was killed doing that job. He was in shorts tennis shoes and a tee shirt putting CT’s on a 3000 amp gear live.
ron
Senior Member
- Location
- New York, 40.7514,-73.9925
Without a study, you can attempt to use the tables in NFPA 70E Table 130.7(C)(15)(a), but even then you need to know the available fault current and the associated clearing time for the breakers.
Essentially pushing the button is equivalent to operating a circuit breaker.
Essentially pushing the button is equivalent to operating a circuit breaker.
NFPA 70E TABLE 130.7(C)(15)(A) PPE Categories For AC Systems | Arc Flash 101
If your equipment is listed here, with the corresponding parameters, you will find the applicable arc flash PPE category and arc flash boundary. TABLE 130.7(C)(15)(a) Arc-Flash PPE Categories for Alternating Current (ac) Systems: Panelboards or other equipment rated 240 volts and below. >...
arcflash101.webflow.io
NFPA 70E TABLE 130.7(C)(15)(A) PPE Categories For AC Systems | Arc Flash 101
If your equipment is listed here, with the corresponding parameters, you will find the applicable arc flash PPE category and arc flash boundary. TABLE 130.7(C)(15)(a) Arc-Flash PPE Categories for Alternating Current (ac) Systems: Panelboards or other equipment rated 240 volts and below. >...
arcflash101.webflow.io
hillbilly1
Senior Member
- Location
- North Georgia mountains
- Occupation
- Owner/electrical contractor
I’ve tried that before, and got it from the poco, but the engineer said they just give out infinite buss, they don’t know the actual available fault current.Without a study, you can attempt to use the tables in NFPA 70E Table 130.7(C)(15)(a), but even then you need to know the available fault current and the associated clearing time for the breakers.
Essentially pushing the button is equivalent to operating a circuit breaker.
NFPA 70E TABLE 130.7(C)(15)(A) PPE Categories For AC Systems | Arc Flash 101
If your equipment is listed here, with the corresponding parameters, you will find the applicable arc flash PPE category and arc flash boundary. TABLE 130.7(C)(15)(a) Arc-Flash PPE Categories for Alternating Current (ac) Systems: Panelboards or other equipment rated 240 volts and below. >...