MEP 660 - Trouble shooting Manual
Doc No.: IM – 51 Rev.2.0 Print: October 2008 1
1.0 INTRODUCTION
The Microprocessor Based Locomotive Control system MEP 660 continuously monitors
operating levels of various parameters like currents, voltages, temperatures, pressures,
PMs etc. and status of all Auxiliary and main contacts of Contactors. The MEP 660
identifies any abnormal working conditions of any equipment that can indicate a fault in
that equipment. Various faults that are identified are given in the Fault Manual document
No. IM 10 issued by M/S Medha Servo Drives. On identification of any such fault, an
appropriate control action is taken instantly to avoid damage to traction equipments. A
fault message, along with any restriction applied due to the fault, is displayed on the
display unit for guiding the driver. The fault is recorded in the error log along with date
and time stamp. Eight data packs of various locomotive parameters are recorded from 5
seconds prior to the occurrence of fault to three seconds after the occurrence of fault @
one data pack every second. These data packs help the maintenance staff later for
analysis of how the fault has developed and also helps analyse complicated faults.
The classification of these faults and their reset procedure are given in Annexure – 1 for
easy reference
This trouble-shooting manual provides information like restrictions imposed by the fault,
probable causes that can cause the fault and the remedial actions to isolate the fault. The
isolation procedures are written for each and every fault message Identified and listed in
the above Fault Message Manual. No troubleshooting guide is required for the fault
recovery messages that are listed in the Fault Message Manual.
There are 19 cards / modules in the MEP 660 control unit. These modules are plug in
type and inserted in the corresponding slots. Through out this manual the slots are
assumed as 1 to 19, from left to right. The card type No. is labeled both on the card and
MEP-660 control unit to avoid wrong insertion of card. A list of cards and their location of
slots are given as Annexure-2
In this manual an attempt is made to explain step by step procedure to isolate the fault
both in locomotive and as well as MEP 660 components. The trouble-shooting manual has
been discussed anticipating that the user has got basic concept on the locomotive,
through knowledge on MEP 660 components and their functionality. It is recommended
that the user should read the system manual document No. 08 and schematics of MEP
660 document No. ED1000 before this document is used.
In the step by step procedure of fault isolation, the user has been asked to perform
Manual testing of inputs and outputs through display unit wherever necessary to find the
status of digital inputs/outputs and proper functioning of out put devices. The procedure
for Manual testing of inputs and outputs are described in the System Manual document
No. IM 08.
Similar way there are three Digital out cards available from slot 14 to 16. The list of
output devices that are connected to each card is given as Annexure – 3 for easy
reference.
There are 5 digital input cards in the MEP 660 control unit from slot 9 to slot 13. A set of
16 inputs are connected to each card through ear marked cables having unique ID nos.
(like ID:xx). The digital input cards MDIP16 are provided with Green and Yellow LEDs on
the front fascia of the card to know the status of the digital inputs. There are 16 green
LEDs on the bottom portion and 16 Yellow LEDs on the top portion of the front fascia. A
number side to the LED identifies these LEDs. The logic between these Green and Yellow
