Relay coordination
Relay coordination
(OP)
Hey,
Needed some help with relay coordination
I have a system whose arc flash study i have already conducted. However, the arc flash level is very high. I have now been assigned the task of reducing the arcing time by coordinating the devices again. I have read IEEE 242 chapter 15 on overcurrent coordination. However, i am little unsure of how to go about changing the relay settings of an already coordinated system. I need some advice.
Thanks
Needed some help with relay coordination
I have a system whose arc flash study i have already conducted. However, the arc flash level is very high. I have now been assigned the task of reducing the arcing time by coordinating the devices again. I have read IEEE 242 chapter 15 on overcurrent coordination. However, i am little unsure of how to go about changing the relay settings of an already coordinated system. I need some advice.
Thanks






RE: Relay coordination
RE: Relay coordination
"The more the universe seems comprehensible, the more it also seems pointless." -- Steven Weinberg
RE: Relay coordination
yes, i am trying to lower the short time settings.
thanks for the advice.
aqua
RE: Relay coordination
RE: Relay coordination
RE: Relay coordination
Differential or instantaneous and/or maintenance settings can provide lower arc-flash, but there are a lot of 480 V systems with main breakers set to max delay and tie breakers set to intermediate. Just lowering the main breaker ST delay down to intermediate can make a big difference while you work at replacing the trip units or incorporating something better.
"The more the universe seems comprehensible, the more it also seems pointless." -- Steven Weinberg