Series-QPC

Supported Applications

The Dwyer Series QPC Quadruplex Pump Controller is designed to alternate four pumps, providing equal run time on each unit. This alternating operation reduces wear and extends the operational life of pump systems. The controller manages five inputs to drive four outputs, ensuring proper function even if one input fails to open or close.

The series supports two distinct sequencing configurations:

• Sequence-on-simultaneous-off (SOSO): An additional load is energized each time a higher level switch activates; all loads de-energize simultaneously when the lowest level switch deactivates.
• First-on-first-off (FOFO): Loads are energized similarly to SOSO, but de-energize individually as each corresponding level switch deactivates.

In both configurations, the lead load position advances automatically to equalize run time. The unit is approved for use in hazardous locations classified as Class I, Group A, B, C, D; Class II, Group E, F, G; and Class III under UL standard 913.

Operating Conditions & Performance

The Series QPC operates on a power supply of 120 VAC, 50/60 Hz with an approximate consumption of 2.5 VA. It features four LED indicators to show which load is currently energized.

• Operating Temperature: -4 to 131°F (-20 to 55°C)
• Storage Temperature: -40 to 185°F (-40 to 85°C)
• Sensitivity: 100 K Ω
• Isolation Voltage: 2500 V (input to output)
• Switch Type: SPST; Switch voltage is 5.1 V open circuit with a switching current of 10 μA short circuit.

The controller includes an inrush delay to prevent multiple loads from energizing simultaneously, reducing line sags. Response times are documented as follows: Power Up <1 s, Operate <25 ms, Inrush 5 s, and Release <150 ms.

Electrical Ratings

The output contacts support an electrical rating of 5 A @ 120 VAC resistive or 278 VA inductive. The maximum distance between the unit and the switch is specified as 1000 feet.

Configuration Options

The Series QPC offers configurable sequencing logic via specific model variants to match system requirements:

• QPC-ASX: Quadruplex Pump Controller with SOSO sequence.
• QPC-ASY: Quadruplex Pump Controller with FOFO sequence.

The unit features surface mounting and includes a polycarbonate dust cover. Electrical connections are made via SPST output contacts. The controller is designed to interface with non-energy storing or generating mechanical switch type devices containing no capacitance or inductance.

Key Product Differences

The primary distinction between the available models lies in their de-energization logic:

• SOSO (QPC-ASX): All loads are turned off simultaneously when the lowest level switch opens.
• FOFO (QPC-ASY): Loads turn off individually as each specific level switch opens, maintaining a staggered shutdown sequence while energization remains sequential for both types.

Both models share identical physical dimensions of 3 in (76.20 mm) height by 3-1/4 in (82.55 mm) width and weigh 16 oz (454 g). Note that the data sheet lists overall dimensions as 4 [101.6] in (width) x 3-1/4 [82.55] in (height) x 3/8 [9.53] in (depth), while the manual specifies a depth of 1-1/4 in (31.75 mm); users should verify mounting space requirements against installation drawings.