Table Appendix B-3 Coil Voltage Vs. Resistor Voltage Rating; Figure Appendix B-2 Transient Suppression In Inductive Coils - Honeywell VPR100 User Manual

Appendix B
Inductive coils, continued
Figure Appendix B-2 is an illustration of transient suppression in inductive coils.

Figure Appendix B-2 Transient Suppression in Inductive Coils

Additional protection may be provided by adding an RC circuit in parallel with the MOV. This consists of a
220-ohm resistor in series with a 0.5 microfarad, 1000V capacitor. The power rating of the resistor will
depend on the voltage rating of the coil (see Table Appendix B-3).

Table Appendix B-3 Coil Voltage vs. Resistor Voltage Rating

115V
230V
460V
550V
300
Metal
oxide
varistor
A.C.
supply
Coil Voltage
VPR & VRX – User Manual
0.5 mfd
1000V
Relay coil
or
220
solenoid
ohms
Resistor Voltage Rating
1/4 Watt
1 Watt
3 Watt
5 Watt
20780
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