Delta RMC101 - Manual (Page 252)

RMC100 and RMCWin User Manual
5-2
for detail.
Figure #1: SSR switching inductive load; high-side configuration
To calculate the maximum current through the SSR in the above diagram, we assume zero SSR
resistance:
Max. current = 24V / 240W = 100mA
Max. current = 5V / 240W = 20.8mA
In the 24V case, the maximum current is right at the maximum allowed by the SSRs. The outputs
may be overpowered if the coil resistance is reduced further. To calculate the typical current
through the SSR, we use the typical SSR resistance of 25W:
Typical current = 24V / (240W + 25W) = 90.6mA
Typical current = 5V / (240W + 25W) = 18.9mA