Maintenance of Unprotected Equipment

We will now understand the maintenance of unprotected equipment. Here, we will also delve into the different types of maintenance.

Types of Maintenance

The technical actions regulate the normal operation of equipment that is divided into two major groups −

  • Preventive
  • Corrective

Preventive/ Predictive Maintenance

Preventive maintenance does not mean to maintain the equipment at the time of malfunctioning but to prevent the failures before it arises. It is applicable to prevent the breakdown. This type of maintenance is performed over a period of time, then it is called as Scheduled Maintenance that reduces the risk of malfunction and degradation of equipment. Preventive maintenance focuses on equipment’s type that manages to adopt predictive and conditional maintenance.

The predictive maintenance defines the equipment status through utilization of various non-destructive testing and measuring techniques. The predictive preventive maintenance program ensures efficient, reliable and safe production.

Corrective Maintenance

When any fault, failure or malfunction is detected, corrective maintenance is applied to the equipment. As the name suggests, it is useful in order to correct the issues. It cannot be pre-determined like preventive maintenance. It focuses on the infrastructure of equipment. It is referred as emergency maintenance. Such maintenance must be carried out efficiently in the equipment.

Preventive Checks

A routine preventive maintenance needs checking to prevent damages in electrical equipment. Consider the checklists given below to follow preventive checks −

Cleaning Machines

Clean the machine at regular intervals and apply oil to the unprotected metal surface.

Lube the Machine

A good lubrication can keep safe the turret, spindle, dry gears, bearings and oil reservoir and protect from wear and corrosion.

Skim oil off the machine

Oil skimmer is used on the surface of the machine to create a perfect breeding ground and removes dermatitis, dry skin, nasty smells and poor tool life.

Monitor machine-cutting fluid

A refractometer monitors the water-based fluid concentration weekly. Another kit checks the PH level. The backlash and alignment should be checked quarterly.


If there is any issue with the maintenance, the equipment requires repairs for smooth functioning. The art of repair facility is responsible to repair and modify all types of electrical equipment parts. There are certain parts of devices that need to be checked frequently and repaired accordingly.


Repairing of leaks, bushings, housings, radiator fins, gaskets and indicators is done and damages can be replaced. Transformer oil will be replaced if the air level is degraded.

Circuit breaker

Obsolete parts should be supplied otherwise, circuit breaker can be replaced. A trained professional should diagnose and ensure the fault.


If there is any tear, accident or electrical fault found in switchgear and control gear by experienced engineers, then repair facility repair the broken parts or replace the equipment.

Protective relay

During troubleshooting, engineer should check if the operation of relay meets the specifications or not. If something wrong is reported, then it is repaired, recalibrated or replaced.


A Cable is an equipment in the electrical system. A single fault in the cable can shut down the whole system. The splicing is checked and the cable is replaced immediately.

Statutory Audit

In case of maintenance, the repairing and replacement process requires some financial support and generation of reports. Thus, statutory audit pitches in. It is to define a fair view of the financial statements such as balance sheet, income and expenditure account, receipt and payment. It shows the distribution of fund regarding electrical material repairing, purchase, etc.

Scope of SA

According to the financial management system, the scope includes −

  • Adequacy of project financial system: Effectiveness of accounting, financing, operation control, compliance with plans, policies, procedures, the reliability of accounting system, data and reports and verifying assets and liabilities.

  • All documents, records and accounts must be kept carefully for a project.


1. Which maintenance is applicable after a fault occurs?

    a) Preventive maintenance

    b) Corrective maintenance

    c) Both A & B

    d) None of these

Ans: b


When any fault, failure or malfunction is detected, corrective maintenance is applied to the equipment.

2. If preventive maintenance is offered monthly, then it is called ______.

    a) Corrective maintenance

    b) Emergency maintenance

    c) Scheduled maintenance

    d) Protective maintenance

Ans: c


When preventive maintenance is performed over a period of time, then it is called Scheduled Maintenance.

3. Which device measures the concentration of fluid?

a) Barometer

b) Thermistor

c) Refractometer

d) None of these

Ans: c


  • Barometer measures air pressure.

  • Thermistor measures temperature.

  • Refractometer measures the concentration of the fluid.