check for a closed circuit across the terminals when the system is at resting pressure

which is standard for many North American industrial facility power grids

Pressure switches must be matched to the OEM water column (WC) rating

It is specifically designed for use with Armstrong Series S and H pumps

Can I use this contactor for single-phase motor applications

Functional Devices PSH75AB10 Power Supply 321894-709 check for a closed circuitThe Functional Devices PSH75AB10 is a versatile 75VA power supply designed for demanding building automation and HVACR control applications. This enclosed multitap transformer features primary voltage inputs for 120, 208, 240, and 277 Vac, allowing for seamless integration into various industrial control circuits without requiring additional voltage step down equipment. The secondary output provides a stable 24 Vac, protected by a dedicated 10 Amp