Single- & Three-Phase | Economy + Heavy-Duty
Helps divert certain power surges away from pump motors and controls. All electrical work must be done by a qualified electrician.
Have a qualified electrician disconnect all supplies, lock out/tag out and test for absence of voltage.
Check phase, actual supply voltage, exact model and safe, code-compliant enclosure clearance.
Choose single- or three-phase and a below-300 V or below-600 V model to match the system. Verify the exact part label and equipment requirements.
Electrician isolates utility and any backup/inverter supplies, applies lockout/tagout, and verifies the circuit is de-energized with a properly rated tester.
Electrician mounts the arrestor in an approved enclosure and follows the current approved wiring diagram for the exact model and equipment. Obtain current Merrill-approved instructions before wiring three-phase units, VFDs or other electronic controllers.
Electrician verifies secure connections, ground/bonding and cover clearance; replaces all covers, restores power safely and checks pump operation.
Heavy-duty: threaded body and nut for panel mounting. Lug versions available. Confirm fit before wiring.
Read these requirements before working on a pump circuit. This guide is not a substitute for approved product wiring diagrams or local electrical code.
Installation by a qualified electrician is required. Disconnect every source (utility, generator, solar/inverter or other backfeed). Lock out/tag out and verify absence of voltage with an adequately rated tester. Never work with wet hands, wet wiring or standing water.
Maintain a code-compliant equipment grounding conductor and bonding path. Verify the pump, control box, pressure switch and surge arrestor are properly grounded. Neutral and a separate ground rod are not substitutes for the equipment grounding conductor.
Verify phase, supply voltage, model and equipment compatibility. The legacy terminal/lead guidance is not a verified three-phase diagram. Get current Merrill-approved instructions before wiring three-phase units, VFDs or other electronic controllers.
Follow the current approved wiring diagram, connection method, conductor size, terminal torque and enclosure rating. Do not pinch leads, leave bare conductors exposed, overload a terminal or force the pressure-switch cover closed. Retain all circuit and motor protection.
After a lightning event, trip, smoke, odor or damage, shut off power and call a qualified electrician. Replace a damaged or suspect arrestor as instructed. A running pump does not prove surge protection works.
Helps divert some voltage surges, but cannot replace grounding, circuit breakers, motor overloads or a complete lightning protection system. Direct strikes and extreme/repeated surges can still cause damage.
ENGINEERING + LEGAL REVIEW REQUIRED
