Our Experience

NTI Bulletin 1998,34/3A4,64-65

repair and maintainence of x-ray units at district    tuberculosis centres


In response to a letter from Deputy Director of Medical
Services regarding improper functioning of patient lift
motor of the MMR X-ray plant of D.T.C. Govt. Head
Quarters Hospital, Dharmapuri, Tamil Nadu, Director,
NTI instructed X-ray section to visit DTC Dharmapuri
for inspection of the X-ray plant and rectify, if possible, the problem faced by that centre.
                               • • •

An advance intimation regarding the time and date of visit of the team from NTI was given to DTC, Dharmapuri for making necessary arrangements. On arrival at DTC, Dharmapuri on 2.7.99, the X-ray technician operating the X-ray unit at DTC, briefed about the problems faced by him in the unit. It was found that the lift motor fuse had blown out and even after replacing the fuse the lift would occasionally move up, but while doing so it would make an unusual loud clattering noise.

The lift motor circuit box was opened and after operating the lift the noise was found to be originating from the HS contactor. Suspecting carbon collection over a period of time, which could be the reason for the unusual noise, the contacts were cleaned with emery and alcohol and the lift was operated, but still the noise persisted when the lift was moving up. The HS contactor could not be replaced with a new one as the same was not available in NTI stoics and it was not available in the local market.

The HS contactor was dismantled completely piece by piece and to our surprise a dead lizard was found sandwiched in-between the main contacts. This was resisting the free flow of current through the contacts and thus resulting in a loud clattering noise. The contactor parts were cleaned thoroughly using emery and alcohol since carbon tetrachloride was not available. The contactor was later assembled, fitted and connections were made in the circuit The lift was operated up and down and the clattering noise disappeared completely. The lift motor shaft was greased with grease gun and later operated up and down several times to check for proper functioning. The limit switches were also checked.

Had the DTC X-ray staff continued to operate the patient lift motor with the problem persisting for a few more days the HS contactor would have been damaged






completely thereby making the lift useless and causing a lot of problem to the patients.

Our advice to all DTC X-ray technicians is not to aperate the X-ray machine when you have noticed any problem in the machine but to immediately report to the DTO of your centre and as per procedure laid down in the X-ray Technicians Manual fill up the 'Report on the condition of X-ray unit' (RCXU) form, get it signed by your DTO, and send it to NTI for further action.

The X-ray section staff of NTI even with limited available resources and experience were successful in servicing the lift motor of the DTC, thereby putting the X-ray unit to best use for the benefit of the patients. „-;.


Conduct periodical checks of X-ray unit

any &,

*     Visual   Inspection:    Inspect   thoroughly   for damages   in    power   cables,   H.T.    cables loose/broken connections.

*      When failure occurs please make sure whether the operating instructions have been strictly followed, the cables are correctly connected, and the fuses are in order. As failures are often due to faulty operations.

Maintenance of RFC Cassette

*       Keep the RFC cassette and the film magazine protected from grease, dust and moisture.

*     Any indentations or scratches on pressure plate will badly affect the definition of the pictures, therefore never place pressure on hard surfaces.

*    Cleaning may be effected periodically with a smooth cloth.

*     The sliding surfaces of the cassette frame also require a great amount of care, any indentations or disfigurement will result in bad fitting in the cassette guides of the camera and hence poor pictures. Avoid