TM  9-6150-226-13 Item No. important  that  any  corrosion  problems  with  DISE and PDISE be reported so that the problem can be corrected  and  improvements  can  be  made  to  prevent the problem in future items. While  corrosion  is typically  associated  with  rusting  of  metals,  it can also include deterioration  of other materials, such as rubber and plastic. Unusual cracking, softening, swelling, or breaking to these materials may be a corrosion problem. If a corrosion problem is identified, it  can  be reported  using  Standard  Form  368,  Product  Quality Deficiency  Report. The form should be submitted to  the  address  specified  in  DA  Pam  738-750. Corrosion can be prevented and controlled by following  PMCS  procedures. NOTE If the equipment must be kept in continuous operation, check and service only those items that can be checked and serviced without disturbing operation. Make the complete checks and services when the equipment can be shut down. WARNING High voltage is present in this equipment. DISE/PDISE supports equipment using 120/208 V ac. Do not perform PMCS with the power on. Death or serious injury may result. Table 4-2. UNIT  PREVENTIVE  MAINTENANCE  CHECKS  AND  SERVICES Interval Semi - annually Semi - annually Semi - annually 4-6 Location Item  to Check/ Service Feeder/distri- bution centers internal wiring M40,M46,M60, M1OO,M2OO, M40 A/P, M60 A/P M100 A/P and M200 A/P Circuit breakers Internal Surfaces Procedure Check  internal  wiring  for  secure connections. Check  for  burnt insulation and signs of over- heating. Check for secure mounting. Check for corrosion and mildew. Not  fully  Mission Capable if: Wires  not  secured by lugs. Wires burnt. Circuit  breaker not secured.