A-B 700DC-PK400Z2 Control Relay

The Allen-Bradley 700DC-PK400Z2 is a heavy-duty industrial DC control relay used for switching and controlling electrical loads in industrial automation systems.

Product Information

• Brand: Allen-Bradley (Rockwell Automation)
• Series: 700DC / Bulletin 700 Control Relays
• Part Number: 700DC-PK400Z2
• Type: Industrial Control Relay (DC coil type)
• Coil Voltage: 230–250 V DC
• Contact Configuration: 4 NO (Normally Open) contacts
• Mounting: DIN rail / panel mount (open style relay base)
• Duty Rating: Heavy-duty industrial control applications (rockwellautomation.com)

Electrical Characteristics

• Coil type: DC operated relay (high voltage DC coil version)
• Contact rating: up to 10–20A depending load category (AC-15 / DC switching duty)
• Contact material: industrial silver alloy contacts for high durability
• Switching capability: suitable for both control and moderate power switching circuits

Function (Simple Explanation)

This device works as an electrically controlled switch bank:

• When coil is energized → all 4 NO contacts close
• When coil is de-energized → contacts open

It allows a low-power control signal to switch multiple independent circuits at the same time.

System Role

Typical control chain:

PLC output / control circuit
→ energizes 700DC-PK400Z2 relay coil
→ relay contacts switch multiple loads
→ drives contactors, lamps, solenoids, or interposing circuits

It is commonly used as an intermediate (interposing) relay in industrial panels.

Typical Applications

• Motor control interlocking circuits
• Multi-load switching from one control signal
• PLC output expansion (signal amplification)
• Industrial machine control panels
• Automation sequencing systems
• Heavy-duty switching isolation between control and power circuits

Key Features

• 4 independent NO contacts (multi-circuit switching)
• Heavy-duty industrial design (NEMA-rated family)
• High DC coil voltage capability (230–250V DC)
• Suitable for demanding industrial environments
• Reliable mechanical switching with long electrical life

Precautions

• DC coil polarity and wiring must follow correct diagram
• Coil voltage is high (230–250V DC), ensure proper insulation and safety
• Inductive loads require suppression (diode / RC snubber)
• Mechanical wear occurs over long-term switching cycles
• Not suitable for high-frequency switching applications