Single Phase Duplex w/ Alternator (SPDAX)

Duplex Pump Control Panel - Single Phase with Alternator (SPDAX)

For higher flow rate systems, M-Tech Control’s Duplex alternating pump controller offers dependable control of dual pump applications across a multitude of industries. Our pump panels are UL508A certified and assembled using Schneider Electric / Square-D components. Single-Phase Simplex control panels are available in 115/120 Volt, and 208/230 Volt configurations.

Each Duplex panel comes with M-Tech’s exclusive 3-year limited warranty. We truly stand behind our products.

Each Panel can be enclosed in your choice of NEMA 4 ANSI 61 painted cold rolled steel, NEMA 4X stainless steel and NEMA 4X non-metallic enclosures. Our Duplex panels can be selected in the configurator below.

Panels include the following as standard:

  • Main disconnect for (2) three phase pump motors.
  • Through the door rotatory disconnect handle. Padlockable for lock out/tag out
  • (2) Motor contactors
    Note: Pump motor must have internal overload protection
  • Electrical alternator
  • Control circuit transformer with primary and secondary protection
  • Control for 2 pumps.
  • (2) Hand-Off-Auto switch. (Located on panel door)
    • Hand – Runs continuously bypassing float switches.
    • Auto – Keeps water level between 2 floats. Floats not included. (1 additional float is required for Lead/Lag operation)
  • Numbered terminal blocks for wiring of float switches.
  • Ground Lugs

All panels are UL listed for the United States and Canada cUL508A

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  • Green pump run pilot light for each pump.
  • High Water Alarm – Float switch not included
  • Red alarm beacon.
  • Auxiliary Dry Contact.
  • Float Switch.

Basic Sequence of Operation

2 pumps working independently (in manual) or through alternation (Auto mode)

  • In Auto – Liquid rises, upper float switch closes and turns on pump 1– As liquid is pumped and level lowers– As lower float switch opens, Pump will turn off.
  • The next time the stop and “lead” floats are closed the alternator will energize pump 2 and will continue until the stop float opens.
  • This cycle will continue to repeat each time the liquid level rises and lowers.
  • (This step only applies if a lag pump float is added to the circuit) If liquid level continues to rise above the lead float after the first pump is energized, the lag float will close and turn on the second pump. Both pumps remain on until the stop float opens.
  • Off – Pump Off
  • Hand – Pump on continuously until switch is turned off

Please contact M-Tech for additional technical and volume price information.

We also offer custom configurations.

skupump quantityvoltagecoil voltagehp ratingenclosure typeenclosure sizepriceQuick ShipQuote
SPDAX-010-1-F-A92120V120V1Nema 4X Non Metallic16 x 14$740.00Quick ShipAdd
SPDAX-020-1-F-A22230/240V120V2Nema 4X Non Metallic16 x 14$793.54Quick ShipAdd
SPDAX-010-1-C-A92120V120V1ANSI 61 Grey Powder Coated Carbon Steel16 x 14$792.57Add
SPDAX-020-1-C-A22230/240V120V2ANSI 61 Grey Powder Coated Carbon Steel16 x 14$846.11Add
SPDAX-010-1-S-A92120V120V1NEMA 4X Stainless Steel16 x 14$1023.65Add
SPDAX-020-1-S-A22230/240V120V2NEMA 4X Stainless Steel16 x 14$1077.19Add

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