Technical FAQs

Ask a Question

What’s the Earth loop impedance value Zs for the GV3 range?

The charts below detail the Earth Loop impedance (Zs) for the GV3 range for any TN system based on the British Standard BS7671:2008+A3:2015

Two documents are also attached:
1) Sheet with Zs charts of Tesys motor circuit breakers:
  • Tesys GV2
  • Tesys GV3
  • Tesys GV4
  • Tesys GV7
  • Tesys U
2) Explaination of the calculation of the maximum Earth Loop Impedancee
This also includes additional information about:
  • Motor Rated devices
  • Ambient Temperature
Tesys GV3 Range
Please refer to the charts below that detail the maximum earth loop impedance Zs for 0.4s disconnection time with Uo 230V
GV3L
Reference Thermal Adjustment
Range In
Magnetic Tripping Current Im Tolerance
Im+20%
Maximum Loop
Impedance Zs
  (A) (A) (A) (Ω) 
GV3L25 25 350.0 420.0 0.52
GV3L32 32 448 538 0.41
GV3L40 40 560 672 0.33
GV3L50 50 700 840 0.26
GV3L65 65 910 1092 0.20
GV3L73 73 1120 1344 0.16
GV3L80 80 1100 1320 0.17
         
GV3P
Reference Thermal Adjustment
Range In
Magnetic Tripping Current Im Tolerance
Im+20%
Maximum Loop
Impedance Zs
  (A) (A) (A) (Ω) 
GV3P13 9 .. 13 182 218.4 1.00
GV3P18 12 .. 18 252 302.4 0.72
GV3P25 17 .. 25 350 420.0 0.52
GV3P32 23 .. 32 448 538 0.41
GV3P40 30 .. 40 560 672 0.33
GV3P50 37 .. 50 700 840 0.26
GV3P65 48 .. 65 910 1092 0.20
GV3P73 62 .. 73 1120 1344 0.16
GV3P80 70 .. 80 1120 1344 0.16
Was this helpful?
What can we do to improve the information ?