Trouble Shooting & Maintenance
Scheduled Maintenance
The S-LX system is designed to be free of scheduled maintenance for its entire service life. No scheduled maintenance regime is required.
Reactive Maintenance
In the rare event of system failure, reactive maintenance may be required to restore the S-LX system to full operation. In the event of system malfunction:
Use the troubleshooting guide below to identify the likely cause.
Refer to the relevant restorative maintenance instruction found later in this guide
If unsuccessful, please contact MPEC Technology Ltd for further support.
Telephone: 01332 363 979. Available Monday to Friday 8 AM to 4 PM UK time.
Email: support@mpec.co.uk. Response typically within 24 hours.
Troubleshooting
Symptoms of identified failure modes are listed below. The “probable cause” field lists fault conditions in order of likelihood and should be eliminated in order. The “Remedial Action” column links to fault finding and maintenance task instructions.
Symptom | Probable Causes | Remedial Action |
|---|---|---|
Total Loss of All Function | AC Power Wiring Fault | |
HZS AC PSU Fault | ||
Total Loss of S-LX compute module | DC Power Wiring Fault | |
HZS DC PSU Fault | ||
S-LX module hardware Failure | ||
Intermittent or Total Loss of Serial Communications | RS232 Wiring fault | |
RS485 Wiring fault | ||
HZS Hardware Failure | ||
S-LX hardware Failure | ||
Electromagnetic Interference | ||
Electromagnetic Interference | ||
Intermittent or Total Loss of Ethernet Communications | Ethernet wiring Fault | |
S-LX hardware Failure | ||
Electromagnetic Interference | ||
Electromagnetic Interference | ||
Intermittent or Total Loss of wireless communication | SIM fault | |
SIM Fault | ||
Sub-optimal antenna placement | ||
Antenna or Antenna cable damage | ||
Wireless Modem hardware failure | ||
SIM card reader Fault | ||
Intermittent or Total Loss of Monitored Signal Function | RS232 wiring fault | |
HZS Hardware Failure | ||
Electromagnetic Interference | ||
S-LX or HZS modules not secured to DIN rail | Loose device fastenings | |
Failed device fastening | ||
Failed device fastening | ||
Physical damage to modules | Impact damage | |
Impact damage | ||
Suspected Earth Fault | Earth cable fitted | |
AC Wiring Fault | ||
DC Wiring Fault | ||
RS232 Wiring Fault | ||
RS485 Wiring Fault | ||
Ethernet Wiring Fault | ||
HZS module Fault | ||
S-LX compute module fault | ||
Intermittent or Total Failure of SD card | SD card fault | |
USB Port Malfunction | Inoperable or physically damaged | |
USB Eject button malfunction | Inoperable or physically damaged |
Reactive Maintenance Instructions
Test and Replace AC Power Wiring
Test | Outcome | Action |
|---|---|---|
Test for voltage either side of the primary fuse | No voltage below fuse indicates blown fuse | Replace fuse |
Test for voltage at AC input plug | No voltage implies a wiring fault | De-energise power circuit and check cables for continuity and physical integrity of all connections. |
Voltage implies HZS device fault | Check mating of power connector and soundness of ferrule crimps. If no fault found, replace HZS device |
Replace HZS Module
De-energise the incoming power supply and test that AC voltage is not present at the HZS power input terminals
Unscrew and remove all device plugs.
The HZS is retained by a sprung steel clip, which will easy pop-off the DIN rail, however loosening any end stops may aid removal.
Replace with a new HZS device by clipping it to the DIN rail.
Tighten any end-stops that may have been loosened.
Reinsert all plugs. Plugs are colour coded and feature cable beads to aid with replacement, but take care to ensure all plugs are reinstalled in their original positions.
Repeat the commissioning steps found in the installation guide.
Test and Replace DC Power Wiring
Test | Outcome | Action |
|---|---|---|
Test for voltage at DC output of HZS device | No voltage indicates failed HZS | Check mating of power connector and soundness of ferrule crimps. If no fault found, replace HZS device |
Test for voltage at the DC input of the S-LX device | No voltage implies a wiring fault | De-energise power circuit and check cables for continuity and physical integrity of all connections. |
Voltage implies S-LX device fault | Check mating of power connector and soundness of ferrule crimps. If no fault found, replace S-LX device |
Replace S-LX Compute Module
The HZS device does not need to be powered down to replace the S-LX device.
Unscrew and remove all device plugs.
The S-LX is retained using two sliding plastic clips at the rear of the device. Withdrawing either top or bottom clip will allow removal of the device from the DIN rail. loosening any end stops may aid removal.
Replace with a new S-LX device by clipping it to the DIN rail.
Your replacement device will have been pre-configured by MPEC to be a direct replacement.
Tighten any end-stops that may have been loosened.
Reinsert all plugs. Plugs are colour coded and feature cable beads to aid with replacement, but take care to ensure all plugs are reinstalled in their original positions, particularly the Ethernet connections
Repeat the commissioning steps found in the installation guide.
Test and Correct RS232 Wiring
Disturbing RS232 wiring in some applications may disrupt the operation of signalling equipment
Check RS232 wiring follows the core assignments that shown in the overlay diagram.
Pay particular attention to pin assignments and soundness of solder connection in DB-9 plugs
Pay particular attention to the soundness of connection made on “punch-down” blocks
Check for secure mating of all plug coupler connections
Check for secure crimping and fastening of terminal blocks.
Test replacement of any pre-moulded “splitter” cables.
Test and Correct RS485 Wiring
Check RS485 wiring follows the core assignments that shown in the overlay diagram.
Check for correct connection of TX and RX RS485 pairs between S-LX and HZS. They are easily swapped.
Check for secure mating of all plug coupler connections
Check for secure crimping and fastening of terminal blocks.
Test replacement of any pre-moulded “splitter” cables.
Screen RS232 Cable
Supplied RS232 cable is screened, however the screen is not connected to a functional earth point.
A functional earth point may be found on the shell of the DB-9 connector of monitored equipment
In this instance, it is possible to connect the cable screen the the plug back-shell.
Contact MPEC is supply of a screened cable is required.
Check and Correct Earth Bonding
Good functional earth bonding can guard against electromagnetic interference.
A functional bond is made by the HZS mounting clip. Where practical, check that a good electrical connection exists between the clip and equipment racking, and that equipment racking is properly earthed.
Functional bonding can also be made by connecting the E terminal of the HZS power connector to a suitable earthing point, using the shortest wiring run possible.
Test and Correct Ethernet Wiring
The simplest way to test Ethernet wiring is to swap out the cable, and then testing both old and new cable to check for faults.
If a known good cable does not correct the issue, check device IP settings..
Screen Ethernet Cable
The unscreened cable must be replaced with a screened cable.
As the S-LX system is isolated from earth, the Ethernet shell on the S-LX device is not connected to a functional earth
The functional earth connection must be made out the non-S-LX end of the cable.
Check Service Provision of SIM
The SIM serial number can be located on the side of the S-LX device
Contact the SIM provider (O2) and check that the SIM is active, and has public Internet access available.
Replace SIM
The SIM resides behind the card-cover found next to the antenna connector.
The cover slides off and held in place with small screw.
Re-site Antenna
Antenna placement has a large bearing on system performance
Even small movements can make a significant difference.
Commercially available signal strength meters, and even personal phones may be used gauge appropriate places to site the antenna.
The S-LX module gives an indication of received signal strength. The indicator only updates once per minute, so patience is required when assessing the impact of any movement
Replace Antenna
Damaged antennas may need like-for-like replacement. Simply unscrew the GSM antenna cable and replace the antenna.
In areas of very poor signal strength, higher-gain antennas may be required. Contact MPEC to discuss.
Check Physical Fitment
Check S-LX retaining clips are securely fastened.
Check HZS device clip is fully locked onto the DIN rail.
Check that end stops are firmly butted against the devices and secure.
Remove Earth Connection
If an earth fault is suspected to be caused by the S-LX system, removal of the earth bonding may reveal the root cause, should the fault disappear.
Replace SD Card
The SD card resides behind the card-cover found next to the antenna connector.
The cover slides off and held in place with small screw.