Electrostar – ComC (communications modules) overhaul

Improving the reliability of communications modules

eTrac’s overhaul service significantly improves the reliability of communications modules by identifying and replacing aging components that are most prone to failure.

Based on robust testing, the main aims are to increase the operational life of the equipment by at least ten years and reduce the number of failures within this period.

Where possible, we fit like-for-like replacements and where components are obsolete, suitable replacements are proposed through a “design query” process.

Communications modules – ‘at-risk’ components

Following more than 15 years of fault-finding and testing we have developed extensive understanding of “at-risk” components that are prone to persistent failures when approaching end of life. Those most likely to require replacement are:

Mechanical components – relays

Wet components – electrolytic capacitors and batteries

Front Line components

Those connected directly to extensive cabling outside the unit (including transceivers)

Critical optical components – optocoupler

Our overhaul process aims to extend the operational life of the equipment by at least ten years and reduce the number of failures within this period.

eTrac’s approach to communications modules overhaul / refresh

On receipt of a module for overhaul the following scope of work is carried out:


Visual check

This comprehensive inspection looks for signs of wear, damage, overheating, liquid ingress and overall cleanliness. Potential obsolescence issues are noted.


Initial testing

The second part of the condition assessment sees units supplied undergo a functional test. Past history will also be considered along with any diagnostic data supplied by the customer.


Repair work arising

Where faults identified during initial checks and testing are unlikely to be resolved by the component refresh, the additional work is communicated to the customer for approval and then completed.


Baseline component replacement

The unit is then disassembled and components identified in the condition assessment are replaced. Where a component is obsolete or unavailable, an alternative of same fit and function is proposed.


Inspection and remedial work

The unit boards are checked for physical defects by an IPC-610 trained inspector. Any solder defects are corrected. The unit assembly will be inspected before its casing is closed.



The casing is closed and any secured. Any missing fixings are replaced.



The unit is powered up and MVB functionality verified using a test bench to simulate interfaces with train-borne equipment. Testing will verify the correct function of all inputs and outputs.

A label will be applied to the back side of the unit casing to indicate completion of the refresh.

For more information on our services and to see how we can help, contact us today on 01483 671544 or fill in our contact form and we'll call you back.