Honeywell 621-6500 (6216500) Product Description

621-6500 (6216500) is an 8-channel, 24V DC source-type (Source) digital output module (DO) of the Honeywell 621 series I/O. It is a standard current, universal 24V DC output module and is suitable for various industrial 24V loads. 

I. Basic Information

Brand: Honeywell (Honeywell / ISSC)

Full Model: 621-6500 (6216500)

Series: 621 Series I/O Module (IPC 620 / 621, TDC 3000, UCN System)

Type: 8-channel 24V DC Source Type (Source) Digital Output Module (DO)

Production Status: Out of Production (Secondhand / Repaired / Reconditioned Channel)

Weight: Approximately 0.45 kg

Dimensions: Approximately 11.8 × 4.7 × 9.4 cm

Installation: Inserted into the 621 Series I/O Rack

Isolation: Channel - System Side Photoelectric Isolation

Common Suffix:

621-6500R: Supports Hot Swap

II. Core Functions

8 channels 24V DC Source Output: Standard 24V Industrial Level, Suitable for Most 24V Loads

Source Type (Source) Output Logic (PNP): Internal connected to the positive pole, outputs high level to drive the load

Photoelectric Isolation: Channel - System Side Electrical Isolation, Strong Anti-interference

LED Status Indication for Each Channel: Real-time Monitoring of Output On/Off

Overcurrent, Short Circuit, Overheat Protection: Built-in Protection Circuit to Prevent Load Faults from Damaging the Module

Standard Current Drive Capability: Single Channel 0.5A, Suitable for 24V Indicators, Relays, Electromagnets

Compatible Systems: IPC 620, IPC 621, TDC 3000, UCN, etc. legacy DCS

III. Electrical Specifications

Output Voltage: 24 V DC Nominal (19.2–30 V DC) Honeywell

Channel Count: 8 Channels (Independent)

Output Type: Source Type / PNP Positive Logic

Single Channel Maximum Current: 0.5 A

Total Current (All Channels): ≤ 3 A

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

Response Time: ≤ 1 ms

Power Consumption: Approximately 4 W

Power Supply: 5V DC (Backplane Bus Power Supply)

Leakage Current: ≤ 100 µA (Off State)

Protection Functions: Overcurrent Protection, Short Circuit Protection, Overheat Shutdown

IV. Environmental Parameters

Operating Temperature: 0°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

LED Indicators:

PWR: Green (Normal Power Supply)

8 Channel LEDs: On = ON, Off = OFF

COM: Red (Common Port Abnormal / Bus Fault)

Bus Interface: 621 Rack-Specific Parallel Bus

VI. Typical Applications

24V Industrial Equipment Control: 24V Indicators, Beepers, Alarm Devices

Intermediate Relay Drive: 24V Small / Medium Relays, Signal Relays

Electromagnetic Valve / Valve Control: 24V DC Electromagnetic Valves, Pneumatic / Hydraulic Valves

Standard Logic Interface: 24V PLC Signals, Digital Interfaces, Instrument Control

Old System Upgrade: IPC 620 / 621, TDC 3000 Systems 24V DO Replacement

VII. Model Comparison (621 Series DO) Table

Parameters: 621-6500, 621-6550, 621-2100, 621-6450

Number of channels: 8 channels, 16 channels, 8 channels, 16 channels

Voltage: 24V DC, 24V DC, 24V DC, 12V DC

Output type: Source type (Source), Source type (Source), Source type (Source), Source type (Source)

Single-channel current: 0.5 A, 0.5 A, 1 A, 0.5 A

Features: 8-point 24V standard, 16-point high-density, 8-point large current, 16-point 12V

VII. Common Faults and Troubleshooting

No output from the channel (LED does not light up)

Reason: Loose wiring, short circuit of the load, module not securely plugged in, bus abnormality

Troubleshooting: Measure terminal voltage, disconnect the load for testing, reinstall the module

LED constantly on (output locked)

Reason: Internal module fault, bus data abnormality, overheating protection

Troubleshooting: Power off and restart, check bus communication, replace module

Insufficient output current

Reason: Overloaded load, module protection triggered, power supply abnormal on the backplane

Troubleshooting: Reduce load current, check module temperature, confirm power supply on the backplane

IX. Related Models

24V DC source type output (8 hot-swappable points): 621-6500R

24V DC source type output (16 points 0.5A): 621-6550

24V DC source type output (8 points 1A): 621-2100

12V DC source type output (16 points): 621-6450

5V DC source type output (8 points): 621-6300

Digital input: 621-4500, 621-4502, 621-4550

Analog input: 621-4000, 621-4001

Analog output: 621-5000, 621-5001