Honeywell 621-2100 (6212100) Product Description

621-2100 is an 8-channel, 115V AC solid-state output module (DO) in the Honeywell 621 series I/O system, used to drive AC loads (relays, solenoid valves, indicator lights, contactors), compatible with the IPC 620/621 control system, and is a fast-switching AC output module. 

I. Basic Information

Brand: Honeywell (Honeywell)

Full Model: 621-2100 (Abbreviation: 6212100)

Series: 621 Series I/O Module (IPC 620 / 621 Rack)

Type: 8-channel 115V AC Solid State Digital Output Module (DO)

Production Status: Out of Production (Second-hand / Repaired / Refurbished Channel)

Weight: Approximately 0.68 kg (1.5 lbs)

Size: Approximately 145 × 100 × 40 mm

Installation: Plug-in into 621 Series I/O Rack

Isolation: Channel - Channel, Channel - System Side Photoelectric Isolation

Suffix R: 621-2100R indicates Hot Swap Support

II. Core Functions

8 Independent Solid State AC Outputs: No mechanical contacts, long lifespan, fast switching

Photoelectric Isolation: High anti-interference, anti-ground current, protecting system side safety

Status Indication: Each channel independent LED (On = ON, Off = OFF)

Fast Response: Suitable for real-time control, high-frequency switching scenarios

Overcurrent Protection: Built-in current limiting, short circuit prevention

Compatible Systems: IPC 620, IPC 621, TDC 3000 and other legacy systems

III. Electrical Specifications

Output Voltage: 115V AC (85–135V AC Effective)

Channel Number: 8 Channels (Independent)

Output Current: 2A / Channel (Continuous); 6A / Common Terminal; 8A / Module

Output Type: Solid State Relay (SSR), no mechanical contacts

Isolation Voltage: 1500V AC / DC (Channel - System Side)

Response Time: ≤ 1 ms (Fast Switching)

Surge Current: 15A (2 cycles, non-repetitive)

Leak Current: ≤ 5mA (Off State)

Voltage Drop: ≤ 2V AC (Conduction State @ 2A)

Power Supply: 5V DC (Backplane Power Supply, Maximum 272mA)

IV. Environmental Parameters

Operating Temperature: -20°C ~ +60°C

Storage Temperature: -40°C ~ +85°C

Humidity: 5–95% RH (No Condensation)

Anti-Vibration: 10–55 Hz, 0.7 mm Double Amplitude

Protection: IP20 (Installed in Cabinet)

Certifications: CE, UL, CSA

V. Interfaces and Status

Field Interface: 50-pin D-Sub / European Terminal

Status LED:

PWR: Green (Normal Power Supply)

8 Channel LED: On = Output ON, Off = OFF

ALM: Red (Overcurrent / Fault)

Bus Interface: 621 Rack-specific Parallel Bus

VI. Typical Applications

Industrial Automation: Drive AC Relays, Electromagnets, Contactors

Power / Metallurgy: Control 115V AC Indicators, Alarm Devices

Chemical / Paper Industry: Pump / Motor Start/Stop Control, Valve Drive

Old System Renovation: Maintenance and Replacement of IPC 620 / 621 Systems

VII. Model Distinction (Confusing)

621-2100: 8-channel 115V AC Solid State Output (No Hot Swap)

621-2100R: 8-channel 115V AC Solid State Output + Hot Swap (R)

621-2101: 6-channel 115V AC Isolation Output (Early Version)

621-1200: 16-channel 24V DC Digital Output (DC Type)

VIII. Common Faults and Troubleshooting

No Voltage Output (LED Does Not Light Up)

Reasons: Loose Wiring, Module Not Enabled, Missing 5V Backplane Power Supply, Overcurrent Protection Check: Measure terminal voltage, check program output, reinsert and re-execute, replace module

Output voltage is low / unstable

Reason: Overloaded load, voltage fluctuation, solid-state relay failure

Check: Confirm that the load ≤ 2A / channel, check 115V AC power supply, replace module

ALM red light alarm

Reason: Overcurrent, short circuit, module internal fault

Check: Disconnect load, inspect wiring, switch slot for testing

Hot-swappable (R type) failure

Reason: Rack does not support hot-swapping, module not securely inserted

Check: Confirm rack model, power off and reinstall

IX. Related Models

DC output: 621-1200 (16 points 24V DC DO)

AC input: 621-1160 (16 points 115V AC DI)

DC input: 621-1500 (16 points 24V DC DI)

Hot-swappable series: 621-xxxxR (R = hot-swappable)