Honeywell HC900 - Replacing the Power Supply

Revision 6 HC900 Process & Safety Controller User and Installation Manual 183
21 April 2017
Table 28 – LED Indications on Scanner Module
Figure 80
item
LED
LED State/Color
Description
1
Scanner Status
Off
Solid Red
Blinking Red
Solid Green
Blinking Green
No power
Failed
(Diagnostic Code; refer to Table 29 -
Scanner LED Diagnostics.)
Startup Mode
Scan Mode
2
3
10/100 Base-T port
XMT (upper LED)
LINK (lower LED)
Green (On/Off)
Green (On/Off)
On while a message is being sent from
the Main CPU; otherwise Off.
On while the Main CPU is receiving a
message. Remains On as long as
host is present; Off when the host is
removed from the link.
NOTE: These LEDs indicate activity on the communication
port, they are controlled by hardware (PHY chip), not by
software.
Scanner Diagnostic LED Indication
The scanner uses its LED to communicate diagnostic information. These diagnostics are a subset of the main CPU’s
and are listed below.
Table 29 – Scanner LED Diagnostics
Number
of
Strobes
Possible Cause
Scanner Action
User Action
1
RAM or ROM failed diagnostics on
power-up.
Executes an infinite loop that toggles the LED.
Communications and module scanning are
disabled. Module outputs are in the power-off
state -- DO outputs are off, and AO outputs
are at zero milliamps.
1. Cycle power
2. Replace scanner
3. Replace rack
4. Check grounding
5. Ensure system is properly
isolated from noise