Three Phase, 3 Leg SCR Power Pak

MaxPac III
Three Phase, 3 Leg SCR Power Pak
  • 120-600 VAC @ 100-1200 Amp
  • Zero Cross-Over Firing
  • Isolated Control Circuit:
       - On/Off Control Inputs: 120Vac, 240Vac, 5-32Vdc Dry contact Closure
       - Proportional (DOT firing) Inputs: 4-20mA, 0-5 VDC, 1-5 VDC, 0-10 VDC
       - Remote Manual Adjust, Remote Auto Manual Switch
  • Flexible I/O Power Wiring
  • Built-In Power Distribution
  • Shorted SCR Detection (option)
  • Easy Customer Interface
  • Remote Shutdown
  • Electronically Protected with Temperature Warning and Shutdown System
  • Compact Size and Construction
  • Touch-Safe (option on 100 to 650 Amp models)
  • dv/dt Transient Voltage Protection
  • MOV Protection
  • Six SCR Full Converter
  • Three Phase Delta, 3-Wire Wye or 4-Wire Wye Connected Loads
  • Single or Three Cycle Resolution (Jumper selectable
  • Third-party certifications: cULus, CE, D

The MaxPac Series is specifically designed for the OEM market. The plug-in options, flexible I/O power wiring, space saving footprint, optional lug kits, I2t fusing and universal approvals make it an excellent candidate for your product.

The Chromalox Model MaxPac III is a Solid State, highly versatile power pak with optional plug-in proportional Firing and Shorted SCR Detection Boards. Firing techniques include: “ON/OFF Power Control” (Contactor) and “Proportional Power Control” (Zero Voltage Switching, DOT fire).

Chromalox’s exclusive DOT (Demand Oriented Transfer) firing switches the fewest number of cycles to provide the most precise zero crossover control. At 50% output the unit’s output alternates between three electrical cycles on and three cycles off. At 51% the output continues with three cycles on / three cycles off and gradually integrates three extra “on” cycle for the additional one percent. With the exception of phase angle firing, DOT firing is the most precise method of SCR control. DOT firing is preferred in many applications because phase angle firing creates unwanted RFI. DOT is excellent for applications where consistent heater/process temperature control is critical.

  • Resistive Heaters
  • Electric Ovens
  • Furnaces
  • Kilns
  • Environmental Chambers

Mechanical Features:

  • LED Indication of Firing
  • Customer Control Connections are made on a Plug-In Screw Type Terminal Block
  • Optional Remote Manual Adjust and Auto/Manual Switch
  • Heatsink Mounted Temperature Sensor
  • Built-In Power Distribution
Electrical Features:
  • PIV 1200V Min at 480 VAC
    PIV 1500V Min at 600 VAC
  • Isolated Semiconductor Power Blocks are used on all Current Ratings up to 650 Amps
Safety Features

Personnel Safety:
  • Ground Potential Heat Sink up to 650 Amps
  • SCR to Heat Sink Isolation up to 650 Amps
  • UL 508 Listed for units 650 Amps and under
  • CE Approval for all units with line filters required.
Equipment/Process Safety:
  • Input to Output Isolation
  • dv/dt Transient Voltage Protection
  • Optional I2t Fusing
  • Remote Shutdown
  • Optional Shorted SCR Detection
For more features refer to catalog page PDF under the Technical Resources tab.

Can't find what you're looking for?