Issue
The datasheet for DO-FA-12 says:
Contact rating .......................250 VAC/30 VDC, 2 A, Pilot Duty (Power Factor 0.35)
What does "Pilot Duty" mean?
Product Line
EcoStruxure Building Operation
Environment
- Building Operation Automation Server Bundled (AS-B)
- Building Operation IO-module
Cause
The datasheet specifies the rating class of the relays.
Understanding what "Pilot Duty" means is needed in order to know what load can be controlled by the relay.
Resolution
A "Pilot Duty" rating means that this relay is made for a specific highly inductive load, such as controlling the coil of another relay or contactor. Contacts with a "Pilot Duty" rating have passed standardized testing to prove they can reliably control a "Pilot Duty" load.
In another example the datasheet of a device may say:
Relay contact rating 250 VAC / 30 VDC, 2 A Pilot Duty (C300)
In this case C300 indicates the rating of the relay, according to the UL 508 standard.
The start current of a motor could damages the relays in case the current is too high. The start current could be up to 8 times the rated current, or more.
