Watlow 988 series User Manual

$5.00
Made in the U.S.A.
Data Communications with the Watlow
Series 988 Family of Controllers
User's Manual
Includes:
981-984 Ramping
986-989 Temperature or Process
996-999 Dual Channel
Watlow Controls
1241 Bundy Blvd., P.O. Box 5580, Winona, Minnesota 55987-5580; Phone: (507) 454-5300;
Fax: (507) 452-4507
W98F-XUMN Rev A03
Supersedes: W98F-XUMN Rev A02
June 1997
Printed on Recycled Paper, 10% Post-consumer Waste.
User Level Targeted:
• New User............................. Go to page 1.1
• Experienced User ................Go to page 2.1
• Expert User .........Go to page 5.1, 6.1 or 7.1
Installer:
• Wiring and installation.........Go to page 2.1
• Setup...................................Go to page 3.1
TL
W
W
A
PROCESS
1A 2A 1B 2B
CH A
CH B
DISPLAY
SERIES 998
MODE
AUTO
MAN
AUTO
MAN
TL
W
W
A
PROCESS
L1 L2 L3 L4
DEV
% OUT
DISPLAY
SERIES 982
MODE
HOLD
RUN
TL
W
W
A
PROCESS
L1 L2 L3 L4
DEV
% OUT
DISPLAY
SERIES 988
MODE

Watlow 988 series Specifications

General

Type	Temperature Controller
Input	Thermocouple, RTD, Process
Output	Relay, SSR, Analog, Linear
Control Mode	ON/OFF, PID
Display	Dual 4-digit LED
Communication	RS-485
Power	24 VAC/VDC
Operating Temperature	0 to 50°C (32 to 122°F)
Enclosure Rating	NEMA 4X/IP65

Summary

About This Manual

Notes, Cautions and Warnings

Details the use of notes, cautions, and warnings for safety and important information.

Technical Assistance

Provides contact info for support and details needed for troubleshooting.

Introduction to Data Communications

Serial Communication Interfaces

Details the technical specifications of RS-232, EIA-485, and RS-422 interfaces.

ASCII and Data Transmission

Covers ASCII character set, parity bits, start/stop bits, and baud rate.

Hardware and Wiring

Serial Hardware Interfaces

Details the controller's available hardware interfaces: RS-232, EIA-485, RS-422.

Wiring Diagrams

Provides detailed wiring diagrams for RS-232, EIA-485, and RS-422 connections.

Communications Setup

Software Protocols and Device Addresses

Discusses protocol options (ANSI X3.28, XON/XOFF, Modbus) and device addressing.

Controller Front Panel Setup

Guides configuring communications settings via the controller's front panel.

Sending Commands

General Message Syntax

Explains the fundamental structure for sending commands to the controller.

Modbus RTU Protocol

Covers Modbus RTU protocol, packet syntax, and commands for data communication.

Command Summary of the Series 981-984

Complete Parameter Download Sequence

Lists the required order for downloading controller parameters.

Ramping Controller Prompt Table

Details prompts accessible in run/hold modes and command syntax.

Command Summary of the Series 986-989

Complete Parameter Download Sequence

Lists the required order for downloading controller parameters.

Temperature/process Controller Prompt Table

Details prompts, syntax, and ranges for temp/process controllers.

Command Summary of the Series 996-999

Complete Parameter Download Sequence

Lists the required order for downloading controller parameters.

Dual Channel Controller Prompt Table

Details prompts, syntax, and ranges for dual-channel controllers.

Appendix

Handling Communication Error Codes (ER2)

Explains ER2 error codes and how to clear them.

User Responsibility

Advises users on proper controller operation and avoiding invalid commands.