Honeywell UDC2800 User Manual

Chapter 11 - Modbus RTU Function Codes 20&21 314
General Information 314
Function Code 20 (14h) - Read Configuration Reference Data 317
Request and Response Formats 317
Byte Count 317
Data Byte Count 317
Reference Type Definitions 318
File Number 318
Register Address 318
Read Configuration Examples 318
Function Code 21 (15h) - Write Configuration Reference Data 320
Write Restrictions 320
Request and Response Formats 320
Reference Type Definitions 321
File Number 321
Register Address 321
Unrestricted Registers 322
Restrictions on Parameter Numbers in One Message 322
Write Configuration Examples 322
Modbus Read, Write and Override Parameters 323
General Information 323
Reading Control Data 324
Read Software Options Status 325
Miscellaneous Read Onlys 326
Setpoints 327
Using a Computer Setpoint (Overriding Controller Setpoint) 328
Configuration Parameters 330
Chapter 12 - Standard Modbus Read, Write and Override Parameters 374
Modbus RTU Message Format 375
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Contents

Honeywell UDC2800 Specifications

General

Control Modes	PID, ON/OFF, Manual
Mounting	Panel Mount
Display	Dual 4-digit LED
Input Types	Thermocouple, RTD, mA, mV, V
Output Types	Relay
Power Supply	100-240 VAC, 50/60 Hz
Communication	RS-485 Modbus RTU
Enclosure Rating	NEMA 4X