Radial Voltage Drop Calculation?... By Load or MCB Rating?

broadgage:

0.285% Voltage drop seems a remarkably low allowance.

5% is commonly allowed, though remember that this is the TOTAL voltage drop from origin to point of use. So if most of this has already been used in a sub main such a low allowance is possible.

 

5 % is only for equipment not covered by a product standard (525.201), or, perhaps socket-outlets for general use - specific equipment (standards or manufacturers instructions) may well be different. See preceding Regulation, and the first one under 525, Regulation 525.1:

 

525.1 In the absence of any other consideration, under normal service conditions the voltage at the terminals of any fixed current-using equipment shall be greater than the lower limit corresponding to the product standard relevant to the equipment.

For example, BS EN 61851-1 for EV charging equipment specifies total - 10 % below nominal, i.e. 4 % in the installation in the UK, not 5 % ... although a manufacturer may permit more.


Appendix 4, section 6.4, volt drop limits (along with Regulations 525.202 and 525.203) applies to Regulation 525.201, equipment not covered by a product standard ... and is "informative" ("guidance") not "normative" ("requirement of the standard").

broadgage:

0.285% Voltage drop seems a remarkably low allowance.

5% is commonly allowed, though remember that this is the TOTAL voltage drop from origin to point of use. So if most of this has already been used in a sub main such a low allowance is possible.

 

5 % is only for equipment not covered by a product standard (525.201), or, perhaps socket-outlets for general use - specific equipment (standards or manufacturers instructions) may well be different. See preceding Regulation, and the first one under 525, Regulation 525.1:

 

525.1 In the absence of any other consideration, under normal service conditions the voltage at the terminals of any fixed current-using equipment shall be greater than the lower limit corresponding to the product standard relevant to the equipment.

For example, BS EN 61851-1 for EV charging equipment specifies total - 10 % below nominal, i.e. 4 % in the installation in the UK, not 5 % ... although a manufacturer may permit more.


Appendix 4, section 6.4, volt drop limits (along with Regulations 525.202 and 525.203) applies to Regulation 525.201, equipment not covered by a product standard ... and is "informative" ("guidance") not "normative" ("requirement of the standard").