Power Switching Devices
POWER SERIES™ Solid State power Controllers
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POWER SERIES™ Solid State power Controllers
Watlow has manufactured solid state power controllers for over forty years. Watlow's POWER SERIES™ is a microprocessor-based product that features application flexibility unmatched by any other silicon controlled rectifier (SCR) power controller on the market today.
Watlow's POWER SERIES controllers include single and three-phase models from 65 to 250 amperes. Field configurable phase-angle or zero-cross firing improves application flexibility on site where needed.
50/60Hz independent operation allows utilization almost everywhere in the world without special calibration considerations. Serial communication via Modbus® RTU allows setup and monitoring of load status from a computer station or control room.
On-board semiconductor fusing improves reliability by protecting the SCRs from heater short circuits. Plus, on-board heater bakeout and control diagnostics can help eliminate initial start up problems. All these benefits are in a touch-safe package that can be quickly and easily mounted in a control cabinet.
Watlow’s POWER SERIES controllers are UL® listed and C-UL® recognized, ensuring that they meet world safety and operational standards.
Features and Benefits
Power Series Features
Features and Benefits
200KA short circuit current rating (SCCR)
Prevents arc flash
Extremely versatile and field configurable
Snap-fit on a pre-mounted plate
Models 65 through 250 amperes rating
Handles a wide range of loads
Adjustable soft start
Provides application flexibility
Heater and control diagnostics capability
Monitors actual heater and controller performance
Electrically touch-safe package
Enhances safety for installer and users
Serial communications with Modbus® RTU protocol
Provides computer control and/or monitoring
Increases application flexibility and reduces panel space
Single-phase, (2 SCRs)
3-phase, 2-leg control, (4 SCRs)
Resistive load only, zero-cross firing only
3-phase, 3-leg control, (6 SCRs)
3-phase, 3-leg control, (6 SCRs) for 4-wire wye loads
Multizone, two and three single-phase zones
Output Control Options
Zero-cross control, fixed time base
Time base one or four seconds with digital programmer
Zero-cross control, variable time base
Phase-angle control and phase-angle control with current limit (not for 3-phase, 2-leg models)
Soft start factory default four seconds upon power-up, and adjustable from 0.0 to 120 seconds
Soft start upon input signal change, output rate of change adjustable to limit max. rate of change from 0.1 to 100% per 0.1 second. Factory default 10%
Current transformer included when required
Line voltage compensated (variable time base and phase angle controllers only)
Standby or non-operational mode
Output Voltage and Current Rating
24 to 120VAC (+10%, -15%)
200 to 480VAC (+10%, -15%)
200 to 600VAC (+10%, -15%)
65 through 250A per pole, model dependent; see output amperage chart and rating curves
Min. load 1A rms ac
Max. leakage current 5mA
200KA SCCR, Type 2 approved with the recommended fusing; see user manual
Single alarm relay
Latching or non-latching
Separate high and low values
Alarm silencing (inhibit) on power up for alarm
Alarm indication LEDs, shorted SCR, open heater, fuse
Electromechanical relay, Form C contact, software configurable
Min. load current 10mA @ 5VDC
Rated resistive loads: 3A @ 250VAC or 30VDC max., inductive load rating 1.5A with a power factor ≥ 0.4 without contact suppression
For single-phase (phase to neutral) and 3-phase 6 SCR models only (not for 3-phase, 2-leg models)
Soft start with over current trip, runs until programmed bakeout time expires, then goes burst or phase-angle firing. Factory default of 24 hours
Adjustable 0 - 9999 minutes with over current trip
Internal current transformer included
Command Signal Input
Field selectable linear voltage and current of low and high points within 0-20mA and 0-10VDC
Manual control input through front panel
Factory default 4-20mA input
Voltage input impedance 11kΩ nominal
Current input impedance 100Ω nominal
On-board digital programmer/display and optional serial communications
Field selectable and scalable within 0-20mA, 800Ω max. or 0-10VDC, load, 1KΩ min. load. The default is 4-20mA
mA ranges = ±5µA
VDC = ranges 2.5mV nominal
mA ranges = ±20µA
VDC ranges = 10mV nominal
Temperature stability: 100ppm/ºC
Digital Programmer/Display and Communications Capabilities
Adjust input and output control type, alarms and soft start, heater bakeout and current limit prompts
Display input and output values along with actual output current
Data retention of digital programmer/display upon power failure via nonvolatile memory
RS-232 for single drop control
EIA-485 for single or multidrop control
32 units max. can be connected. With additional 485 repeater hardware, up to 247 units may be connected
Modbus® RTU protocol
1200, 2400, 4800, 9600, 19200 baud rates
Controller Power Supply
Universal line voltage input range 100 to 240VAC (+10%, -15%) at 55VA max.
50/60Hz ± 5% line frequency independent
Controller line voltage for electronic power supply can be run on separate line voltage
Natural Convection and Fan Cooled Models
Cabinet venting may be required
Power Dissipation (Watts)
Approximately 1.25 watts/amperes per controlled leg
Command signal to load and line/load to ground 2200VAC min.
On-board semiconductor fuses provide SCR protection
Mounts on a removable subplate
Heat sink fins must be mounted in vertical orientation
High Current Terminals
3/8 in. (10 mm) Allen head compression terminals will accept #6 AWG to 350 MCM wire. Allen wrench adapter (included) for 3/8 in. (10 mm) socket, 6 point only
Torque to 180 in.-lb (20.3 Nm)
Wire strip to 1 1/8 in. (30 mm)
Requires 194ºF (90ºC) wire insulation rating on line and load terminals
1/8 in. (2.5 mm) blade screwdriver, accepts 12-22 AWG or 2 No. 22-18 AWG wires
Torque to 8 in.-lb (0.9 Nm)
Wire strip to 0.24 in. (6 mm)
122ºF (50ºC) base rating
32 to 140ºF (0 to 60ºC) fan cooled
32 to 149ºF (0 to 65ºC) natural convection cooled
0 to 90% RH (relative humidity), non-condensing
Meets EN50178, Pollution degree 3
-40 to 185ºF (-40 to 85ºC)
23 lb (10.3 kg)
UL® 508 listed, File #E73741, Vol. 3, Sec. 2
C-UL® listed to C22.2 NO. 14
CE 2004/08/EC (EN61326-1), Class A with filter, CE 2006/95/EC (EN50178)
Power Series Features
Removable Mounting Plate
POWER SERIES snaps on a pre-mounted, removable subplate.
Electrically touch-safe package.
Slides up and down for fuse maintenance and covers the high voltage components.
For controller configuration, setup and monitoring features.
Built in, designed for easy ground connections.
Input, retransmit output, communications and alarms.
Is integrated into the package on forced air cooled models to eliminate separate power connection for fan.
Used to torque terminals one to six and ground lug.
This configuration can be purchased with any or all the features available on the POWER SERIES, based on customer preference. It is intended for resistive heaters, but can also be used on transformer connected loads in the phase-angle firing mode.
Three-Phase, Two-Leg Configuration
This configuration is intended for zero-cross firing only into a stable resistive heater. Typically, a three-phase delta or ungrounded wye connected heater is used and only two of the three VAC line phases are switched. The third phase is a direct connection through a bussbar on board the POWER SERIES. Heater current monitoring and kVA options are available via the heater diagnostics option.
Three-Phase, Three-Leg Configuration
All POWER SERIES options are available with this configuration. It works well with phase angle firing into a three-phase, three-wire wye or delta connected heater. In this configuration, the more common applications are transformer connected loads with heaters requiring a soft start and/or current limiting.
The three-phase, four-wire configuration is intended for zero cross firing into a three-phase grounded wye/star heater (This is a separate hardware option, model number dependent.)
Single-Phase, Multizone Configuration
This configuration is available in two and three single-phase zones and all the features of a single-phase unit are available. (Note that there is only one alarm relay and all zones in the controller must use the same control method.)
Heater diagnostics may include some or all of the features that require heater current monitoring, depending on the model selected. Heater current monitoring is only available with heater diagnostics installed on the controller. The features dependent on heater current monitoring are heater bakeout, current limiting, heater kVA monitoring, retransmit and heater monitoring alarms such as open heater, heater out of tolerance, load balance and shorted SCR detection/error. Heater diagnostics must also be installed if you need phase angle control with current limit.
Package Style C Dimensions
Mounting Plate Dimensions
POWER SERIES Features