ECCJ / Text / Thailand / Standards of Judgment for Energy Conservation Act and Successful Improvement Cases(Energy Conservation of Electrical Facilities)

5.1.6

4 Studies of problems
4-1 Stand-by electricity when machines are not used (awareness of operators)
Electricity consumption had been known only at each factory until the problem was taken up. Even when machines were not used, the power supplies were left turned ON and standby electricity kept flowing wastefully. It had not been perceived how electricity was wasted and how much was paid for wasteful consumption. Especially, being busy or working overtime, they would leave the nonoperating machines with the power switch turned on.
4-2 Waste of air compressors
After checking the hourly electricity consumption, it was found that the consumption did not always correspond to the operation of machines which supply air. Even when it corresponded to the operation, electricity was consumed more than necessary. The causes were as follows:
- (a) Leakage due to aging of pipes
  (b) Request for air from machines which were not working (it was found that wire electric discharge machines periodically requested air even after finishing the process)
  (c) Mismatched combination between compressor and machine group (Piping was not made according to operative conditions, so when only one machine was started at night, a large compressor would start)
4-3 Characteristics of wire electric discharge machine
It was not designed to automatically turn off the power switch after finishing processing. So it kept wasting the standby electricity until operators turned off the switch.

5.1.7

5 Contents of corrective measures
5-1 Stand-by electricity when machines are not used (awareness of operators)
- [1] The company installed electricity measurement devices on 100 electric machines, which are equivalent to 80% of electricity consumed in the company, and started to classify the electricity consumption into wasteful and useful using dedicated software.
  [2] Measurement was made every minute. Daily operation records and consumption of standby electricity were controlled for each equipment, using an operation control chart known as the “Othello Chart.”
  [3] These data were compiled on monthly basis for each equipment. Additionally, performance record was strictly controlled as information on each equipment group.
  [4] The company clarified the divisions which were good at cutting the standby electricity and the division which were not, comparing with the consumption in January 2004 as the reference point and gave the information to each operator with their pay slip.
  [5] The electricity fee thus saved was equally distributed to each operator as “energy conservation dividend”.
  [6] As a result, this system was supported by employee’s families and became encouragement for improvement activities.
5-2 Waste of compressors
- As well as checking the joints of pipes, old pipes were changed to new ones. As a result, air leakage from pipes was eliminated, and air supply to machines which are not requesting air was minimized.
5-3 Mechanical characteristics of wire electric discharge machine
- The design was changed to the one that automatically cuts the power supply after processing.

5.1.8 Image of the system to identify and visualize useful and wasteful power consumption

5.1.9 Othello chart (checking operation status every minute)

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