Protection study on existing LV network with obsolete equipment
Protection study on existing LV network with obsolete equipment
(OP)
A client who recently had a factory burn down following an electrical fault has asked me to carry out a discrimination study across his network at another plant. The supply is comprised of a 300kVA 400v TPN supply, MCCB main switchgear with 15 downstream type B MCB sub main boards.
The problem is most of the kit is out of date and few details are available for the performance of the devices, the equipment is by a number of manufacturers and the fault levels are highish.
I have measured the FLs at the source and at all 15 boards and final circuits and am ready to carry out the study but I am unable to find certified coordination data relating to the obsolete devices.
Consequently, I am stuggling to I predict with any real confidence the performance of a circuit, for example, comprised of a 400A HRC fuse in series with an obsolete 250A Hager MCCB in series with an obsolete 100A MEM MCCB with a FL of 6kA flowing.
Any thoughts ?
The problem is most of the kit is out of date and few details are available for the performance of the devices, the equipment is by a number of manufacturers and the fault levels are highish.
I have measured the FLs at the source and at all 15 boards and final circuits and am ready to carry out the study but I am unable to find certified coordination data relating to the obsolete devices.
Consequently, I am stuggling to I predict with any real confidence the performance of a circuit, for example, comprised of a 400A HRC fuse in series with an obsolete 250A Hager MCCB in series with an obsolete 100A MEM MCCB with a FL of 6kA flowing.
Any thoughts ?






RE: Protection study on existing LV network with obsolete equipment
Rafiq Bulsara
http://www.srengineersct.com
RE: Protection study on existing LV network with obsolete equipment
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