Watlow QPAC Specifications

QPAC

TOTAL

3 Year Warranty

CUSTOMER

SATISFACTION

Modular SCR Power
Controller for Custom
Tailoring to the Application

The QPAC SERIES from Watlow® is a modular Silicon
Controlled Rectifier (SCR) power controller with plug-in
features for flexibility. Bases are rated from 150 to 1000
amperes in one-phase, three-phase, two leg and three-phase,
three leg.

A variety of transformers from 120 to 575VAC along
with 50/60Hz operation enable the QPAC to operate in
applications anywhere. Plug-in control cards set the
QPAC’s SCR firing modes; solid state contactor, burst
firing (zero cross) or phase-angle models are available with
a wide variety of options. This power controller includes 200KA
short circuit current rating (SCCR) and high speed fuses to
minimize damage in the event of a short circuit.

Typical Applications

• Furnace and ovens

• Petrochemical

• Heat treating

• Duct heating

• Environmental chambers

• Kilns

Features and Benefits

200KA short circuit current rating (SCCR)

•

Minimizes damage in the event of a short circuit

Modular power controller

•

Unit base can be fitted with a variety of plug-in

transformers and control cards

Available in 150 to 1000 ampere ratings

•

Handles large or small loads

Available in solid state contactor, burst firing
(zero cross) or phase-angle fired mode

•

Meets most application requirements

Rugged design for 122°F (50°C) ambient operation

•

Full rating of the power controller can be used in

industrial applications

Semiconductor fuses and snubber protection included

•

Protects the SCR from voltage or current surges or spikes

Open heater or shorted SCR detector option

• Diagnostic capabilities

UL® 508 listed and C-UL® up to 1000 amperes

•

For applications requiring agency approvals

© 2013 Watlow Electric Manufacturing Company all rights reserved.

®

WIN-QPAC-0613

Specifications

Operation
Modular controller base with plug-in card and

transformer

• Plug-in control cards
Solid state contactor, dc input
Burst fire control, fixed or variable time base
Phase-angle fire control
Phase-angle control with soft start and current limiting

• Plug-in transformers (50/60Hz)

• 120, 208, 240, 380, 415, 480, 575VAC operation

Power bases

• 1-phase (Q01), 1 pair of SCRs

• 3-phase (Q32), 2 leg control, 2 pair SCRs
Resistive load only, burst firing only

• 3-phase (Q33), 3 pair hybrid SCRs/diodes
Recommended for phase-angle only with balanced load

Agency Approvals

• UL® 508 and C-UL® listed, 150 to 300A all configurations,
File #E73741

• UL® 508 and C-UL® listed, 400 to 1,000A on Q01 and Q32,
up to 480VAC

Control Card Inputs
(CD) Solid state contactor, dc input

• On, 4-32VDC; off, 0.5VDC

• Built-in noise reduction network

(BF) Burst firing control fixed time base

• Process input factory set @ 4-20mA DC

• Input impedance 250Ω (clip resistor for 5kΩ impedance
voltage input), or manual control input

• Time base 4 seconds (clip resistor for 1 sec)

(BV) Burst firing control, variable time base

• Process input factory set @ 4-20mA DC

• Input impedance 250Ω (clip resistor for 5kΩ impedance
voltage input), or manual control input. Requires an
accessory bias and gain card to calibrate for 0-5VDC input

(AF) Phase-angle control

• Process input factory set @ 4-20mA DC

• Input impedance 250Ω (clip resistor for 5kΩ impedance
voltage input), or manual control input

• Soft start approximately 6 seconds upon power-up,
1 second upon set point change

(AL) Phase-angle control with current limit

• Process input factory set @ 4-20mA DC

• Input impedance 250Ω (clip resistor for 5kΩ impedance
voltage input), or manual control input

• Soft start approximately 10 seconds upon power-up,
1 to 2 seconds upon set point change

• Current transformer included

Open Heater/Shorted SCR Detector

• Zero cross/burst fire models only

• Triac output

• 24 to 240VAC, 300mA @ 77°F (25°C), 125mA @
176°F (80°C)

• Energizes on alarm

• Holding current 200µA min.

• Latching current 5mA typical

Outputs

• 120 through 575VAC

• 1, 2 or 3 pole

• 150 to 1000A per pole

• SCCR, 200KA with original equipment specified
semiconductor fusing

Line Voltage / Power

• 50/60Hz ac line frequency, Q32 and Q33 models are
50/60Hz calibration dependent

• Voltage: ±10%, 120, 208, 240, 277, 380, 415, 480,
575VAC

Line Voltage Compensation

• 10% ∆ in line, 2% ∆ in load in the 30 to 70% power region
(AF, AL and BV)

Power Dissipation (Watts)

• 1.5 W/A per controlled leg

Isolation

• Command signal to load 1250VAC min.

Linearity

• 2%, 30 to 70% power region (All units except CD)

Off-State Leakage Current

• 20mA @ 480VAC

SCR Protection

• Semiconductor fuses provided dv/dt 200V/µsec min.

• MOV1 and RC snubber network standard

• (Q32) 3rd leg fuse kit may be used, but not required, with
3-phase, 2 leg models

Mounting

• Heat sink fins must be mounted in vertical orientation

Operating Environment

• 32 to 122°F (0 to 50°C)

• 0 to 90% RH, non-condensing

• 2,000 meters altitude

Storage Temperature

• -40 to 185°F (-40 to 85°C)

Options

• Manual Control Kit for process input cards
(1kΩ potentiometer) #08-5362

• 240VAC and 120VAC cooling fans

1

MOV comes only on Q33 (3-phase, 3 leg).

QPAC Weight Chart

Phase

Amps

150 15 (6.8) 36 (16.3) 50 (22.7)

200 15 (6.8) 36 (16.3) 50 (22.7)

300 15 (6.8) 36 (16.3) 50 (22.7)

400-600 44 (20.0) 85 (38.5) 100 (45.4)

800-1000 49 (22.2) 120 (54.4) 135 (61.2)

1Ø/Q01

lb (kg)

3Ø, 2-leg/Q32
lb (kg)

3Ø, 3-wire/Q33
lb (kg)