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EXcel4 Controller
06.28.06.19
4
Trouble-shooting
4.1
Fault-finding communications problems
EXgarde will indicate if it has failed to communicate with any ACU, and the red and
green LEDS on the EXcel
4
boards can be used to assist with troubleshooting. Note that
this type of problem is more easily resolved by disconnecting the RS485 connections from
ALL EXcel 4 units and trying to bring them on-line one at a time
–
a faulty connection at
one unit could prevent communication with all units.
Red LED flashing
rapidly, green LED
flashes every 1-5
seconds
Normal behavior by EXcel
4
–
if EXgarde software reports ACU as “off
line” then data transmitted by EXcel is either not reaching the PC or the
EXcel
4
A and B TX (transmit) data lines are reversed.
No LEDs flashing
Data transmitted by PC is not reaching EXcel
4
Only RED LED
flashing
Data transmitted by PC is reaching EXcel
4
but either EXcel
4
serial
number has not been entered correctly or the EXcel
4
A and B Rx
(receive) data lines are reversed
A diagnostic tool
–
eXmonitor.exe
–
is available for Rs232/RS485. This will display a list of all
units that are capable of communicating correctly and provides a quicker, simpler way
of troubleshooting. The tool is installed automatically in the EXgarde program directory,
but with no shortcut
–
run it directly from the folder.
4.1.1
Controller Identification
The easiest way to identify your EX series controller is on the 1st digit of the UID number
written on the UID square processor on the main PCB.
The UID takes the form of 1-000-100-123 where the first digit identifies the EX series ACU
type: 1 = EXpert, 2 = Expander, 3= EXcel
2
, 4 = EXcel
4
, 5 = MICROgarde 2, 6 = MICROgarde
1. On the Main White Cabinet (Case) of the ACU is a label at the top stating the product
type, but should an engineer swap the PCB’s or add additional ones this may b
e
inaccurate.
4.1.2
Controller Losing Memory
The first thing to check is that the Memory battery has been enabled.
If the ACU has been left down powered for a very long period of time with the
Memory battery left enabled then eventually this battery may need replacing,
measure the voltage across the battery for a minimum of 3V. In “normal” operating
conditions this battery will last at least 10 years.
Lack of suppression across peripheral equipment containing a coil, may induce back
EMF (spikes) which could potentially affect the PCB and thus erase programming in
the RAM. Such effects can cause permanent damage to the circuit.
