Woodward MicroNet TMR 5009FT, Инструкция по установке и эксплуатации оборудования

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Manual 26518V2 5009FT Installation/Hardware
Woodward 36
Using the graph in Figure 4-15, the intersection point between the 200
Ω load resistance line and the 110
Vac line was found. From this intersection point it was determined that the voltage developed across the
load due to leakage current (when the relay is open) is approximately 7.5 Vac. This voltage level is lower
than the load’s 25 Vac drop-out voltage, thus Latent Fault detection can be used with this example circuit.
If, however, the load resistance was 1200
Ω , the intersection would be approximately 29.5 Vac too high
for LFD. By following the graph along the 25 Vac line to the 110 V line, a total load resistance of 900 Ω is
needed. By placing a properly rated 3600 Ω resistor in shunt with the load, (1200//3600  900) LFD can be
used.
Figure 4-14. Latent Fault Detection Verification Graph—18–32 Vdc Circuitry
Released