Honeywell HC900 Benutzerhandbuch

Diagnostics and Troubleshooting - User Interface

138

HC900 Hybrid Controller Installation and User Guide

Revision 5

9/03

Table 30 - Scanner Diagnostics

Diagnostic
Condition

Number
of
Strobes

Possible Cause

Scanner Action User

Action

High CJ
temperature

Possible reasons for this
diagnostic are:

1. One of the two CJs on the

module is indicating a
temperature reading greater
than 70 degrees C.

2. Both cold-junction sensors

are failing to convert.

3. The CJs are converting

properly, but their differential
is greater than 10 degrees C.
(will be confirmed through
experimentation).

No action is taken.

1. Improve ventilation to rack

2. Replace AI module

Wrong module

The module does not agree with
the module required for the
control scenario.

No action is taken.

1. Verify configuration

2. Replace module with the

correct one.

No communication
to the module.

The scanner is unable to
communicate to the module for
one of the following reasons:

Module is not installed

Backplane problem is inhibiting
the scanner to properly
communicate with the module

No action is taken.

1. Verify configuration

2. Install or replace module.

3. Check for bent pins on the

module.

4. Replace the backplane.

Bad channel

No action is taken

Bad module

Module is reporting a diagnostic
condition. See Table 28 - Bad
Module Diagnostics.

No action is taken.

User should inspect the module’s
status LED to determine the
nature of the problem. The table
in Table 28 - Bad Module
Diagnostics describes the user
action for the various LED
diagnostics.