- Pressure
- Pressure sensor preset to 20 psi, fitted in the pump case or the mainline just downstream of the pump. The temperature sensor shuts the pump down above 105 degrees at the pump housing
- Connection
- ¼" NPT for the pressure sensor and the optional temperature sensor — the LP series pump has ports for both. Wires to the master valve and common terminals of any AC lawn controller
- Sizes
- MPLC24 (pressure sensor) · MPLC24T (adds temperature sensor) — add G for grey or S for unpainted stainless to the model number, so MPLC24S and MPLC24TS are the stainless builds. Signal voltage 24, 110 or 220 VAC. The standard 40 A relay starts a single-phase pump to 5 HP; the family reaches 10 HP through the thermal-protection models (3, 5, 7½ and 10 HP max), and three-phase or larger is a custom build. Electrical rating 120 V 24 FLA / 240 V 28 FLA, 5 kA short-circuit. Replacement parts: ELRELAY1D contactor (24 V, 40 A, DIN rail), ELTIMER1 on-delay timer (0 s–10 min), ELSWITCH2 20 psi pressure sensor, ELTEMP25 temperature sensor
- Best for
- A pump start relay that also protects the pump. The pressure sensor catches run-dry and loss of prime before the seals go; the temperature sensor catches a dead-head, where the pump keeps running against a closed discharge and cooks the pipework and PVC. Compatible with all major AC controller brands, and all power leaving the box is 24 V rather than line voltage. UL and cUL listed, NEMA 3R enclosure. The time delay is factory set at 30 seconds and is field adjustable — a large zone or a first fill may need longer. A reduced-incoming-amperage version suits controllers whose pump-start output is under 0.35 A
