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•  Using the Latest Microcontroller based Technology.

•  Programmable C.T. range of 25/5 to 200/5.

•  Smooth and reliable change over to Delta, when load goes above set current .

•  Compact size and easy to install.

•  “ADD-ON” unit between existing Star Delta starter & motor.

motor energy saver
link to download-brouchure

•  Built-in watch-dog circuit for Fail Safe operation.

•  Program setting by three soft membrane keys on the front panel.

•  Advanced Microcontroller based technology, inherently more reliable and accurate.

•  Direct digital display of current drawn by load.

•  Delay timer 1-999 seconds for Delta to Star change over.

•  Timer setting for initial Star to Delta and Delta delay time.

•  Time setting for Hysterisis (change over delay from Star –Delta and Vice versa).

•  Optional features for Overload tripping with settable Amps and tripping time.

•  Star / Delta run indication on front display

•  On line power monitoring system (optional)

•  Working with KW setting also (optional)


In any industry, the electrical motor accounts for 55% to 60% of the electrical energy consumption Induction motors operate efficiently as long as they are loaded up from 60% to 85% loading. When these motors are operated below 50% loading, the Efficiency and Power Factor is very low. During lightly loaded condition (less than 50% loading), it is preferable to run motors in Star mode instead of Delta mode, and this reduces your Electrical Bill.


•  Voltage across winding reduces to 58% of rated voltage and line current reduces to 1/3 rd . Thus reduction in iron and copper losses, hence Less Power Consumption, Reduced Power Bills.

•  Improvement in Power Factor and Efficiency

•  Energy saving from 5% to 35% possible depending on percentage of loading of motor (No Load to 50% loading.

At 50% load minimum saving and at no load maximum saving).

•  Decrease in line current which gives additional savings in cable losses and losses in switch gears.

•  No need of changing motor to lower KW rating.


•  Under loaded equipment like pumps, blowers, agitators, ball and roll mills etc., or In process where load varies at different stages (3 phase machine s only).in all the Industries.

•  Particularly in Textile spinning machines – Blow room Beaters, Carding cylinder motors (all type), Ring frame main motor (LG 5/1), and Humidification plant motors (Exhaust and Supply Air Fans).

•  Machine shop industries: Like Lathe machine, Power Press, Drill M/C, Boring M/C. etc., (3 phase machines only).

•  I/D Fans, F/D Fans.


Load Sensing : 0 to 5 am ps through current transformer (CT)

Range : Programmable range is possible with built in scale factor.

50/5, 100/5, 150/5.

Setting : By 3 keys on front panel i.e., (Set/Enter), (Increment), (Decrement / Reset).

Display : 3 Digits of 13 mm. Bright light L.E.D. Display.

3 nos.Red L.E.D. for Relay ON indication.

Hysterisis : 0 to 99 count

Initial Star to Delta

Change over time : 1 – 99 second delay according to the usage.

Delta delay time for load

Sensing and change over : 1 – 999 second delay, wherever applicable.

Overload relay setting : 1 to 99 Amps setting for current

1 to 99 Second setting for trip time

Output : 1 NO/ 1 NC Relay contact rated 230V / 6 A for both relays (1 & 2.)

Supply : 230V AC +/- 10%, 50 Hz.

BEE Guidelines on ENERGY SAVING in Under-Loaded Star-Delta Connected Motors .

figure show efficiency and power factor
Fig. shows the Efficiency, Power Factor, Speed and Current vs. Motor Shaft Load characteristics in both Delta and Star connections of the Motor.

•  'In Delta-Connection', the line voltage is impressed on each motor phase winding. Whereas in ‘star connection', line voltage divided by _/ 3 is impressed on each phase winding.

•  The vertical dark band (40 to 50% loads) is the ‘Changeover' region, which differentiates possible Delta operating zone (right hand side) and Star operating zone (left hand side).

•  Observing the efficiency curves, it is clear that at light loads (30% or less); operation of motor in Star connection can save energy, as motor efficiency is significantly better.