A maximum demand meter is a meter used to measure the maximum demand of a consumer i.e maximum amount of electricity consumed over specific period of time usually quarter or half an hour.
Purpose of Maximum Demand Meter
Maximum demand meter helps business suppliers to measure the peak energy consumption of their consumers which helps in efficient and reliable energy supply reducing overall energy cost. With the help of peak demand period, suppliers can plan their generation and distribution efficiently reducing the need of devices, machines and infrastructure reducing overall capital cost.
Maximum demand meter helps consumers to reduce their electricity bills by reducing peak power usage as higher rate will be applied during peak period. It also in planning appropriate backup power source.
In short, the primary purpose of maximum demand meter is to reduce overall capital cost and electricity bills.
Operation or Working of Maximum Demand Meter
In the maximum demand meter, the measuring current flows through the bi-metal spiral which is temperature sensitive. The free end of the spiral is connected to a black measuring pointer. The moving system is activated by heat generated by the current flowing through the spiral. The instrument is provided with an additional red slave pointer with a higher friction which makes it to remain at its maximum position which determines the maximum average loading current.
The high torque of metallic movement drags the red pointer along with the black pointer. The red pointer remains stationary at the maximum value reached. This can be reset by rotating the knob provided on front facia. To prevent false indication due to fluctuations in ambient temperature, an additional bimetallic spiral is wound in opposite direction, which is mounted on the same spindle to compensate variation in temperature from -10 to +55 degrees Centigrade. Frequently there is a need to measure instantaneous current simultaneously & hence moving iron movement having the same range is incorporated in the same meter.
Application of Maximum Demand Meter
They are primarily used where there is substantial variations in power demand throughout a day. The main applications of maximum demand meter has been listed below.
- Industrial and Commercial Sector
- Hospitals
- Large Buildings
- Shopping Malls
- Factories
Disadvantage of Maximum Demand Meter
The main disadvantages of maximum demand meter has been listed below.
- Complex Design
- High Cost