Three Phase Duplex w/ Alternator (TPDAX)

Duplex Pump Control Panel - Three Phase with Alternator (TPDAX)

For higher flow rate systems, M-Tech Control’s Duplex alternating pump control panels offer dependable control of dual pump applications across a multitude of industries. Our pump panels are UL508A certified and assembled using high quality components. Three-Phase Duplex control panels are available in 208/230 Volt, 460V and 575 Volt configurations.

Each Duplex panel comes with M-Tech’s exclusive 5-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
  • (2) Motor protection switch with overload for three phase motors.
  • Control circuit breaker
  • 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
  • NEMA 4/12 ANSI 61 painted cold rolled steel, NEMA 4X 304 Stainless Steel, or NEMA 4X non-metallic corrosion resistant enclosures are available. (316 S/S upon request)
  • 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)

  1. 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.
  2. The next time the stop and “lead” floats are closed the alternator will energize pump 2 and will continue until the stop float opens.
  3. This cycle will continue to repeat each time the liquid level rises and lowers.
  4. (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.
  5. Off – Pump Off
  6. 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.

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