DD28 Meter is aplicable for single phase active energy measurement, it is designed to meet IEC60521 standard for indoor and outdoor installation
1. Case
1. 1 base: Steel sheet
Weather proof steel sheet
1. 2 meter cover: It is made of ABS material, flame resistand, in black colour with glass window. Meter cover can also be made of transparent glass, weather proof, and transparent plastic.
1. 3 terminal block: It is made of phenolic resin, flame resistant, in black color, voltage link can be inside the meter base or outside the meter base.
Terminals are made of brass having two screws for tightening the external cables
1. 4 terminal block cover
Short steel cover rubber underside the cover assures insulation between the cover and the terminal block
Short ABS cover non flammability of ABS, cover conforms to requirements of IEC60521
Extended steel cover rubber underside the cover ensures insulation between the cover and the terminal block, access is available at each side of the terminal cover for external cables
2. Driving element
Current electromagnet
The overload compensating set mounted on the laminated silicon steel core assures the excellent load curve performance
Voltage electromagnet
The design of voltage electromagnet permits to withstand the impulse voltage of 6kv
3. Braking element
Braking element is made of monopolar magnet, its adjustment range comforms to requirements of IEC60521
4 Frame
The meter frame is made of aluminum alloy with sufficient strength, it is painted for effective protection against corrosion
5 Moving element
Worm gear on the rotor shaft is made of brass or optionally plastic one,
Anti creeping pin is fitted to the rotor shaft to prevent running with no load
Anti reverse device can be mounted in the meter if it is required
Upper bearing
With excellent friction resistant property the upper bearing pin is of polished stainless steel to guide the rotating of the disc
Low bearing (optional )
Double jewel bearing
Magnetic bearing with metal enclosure
Magnetic bearing with transparent enclosure the bearing enclosure is made of transparent polycarbonate
6. Register
The register is of cyclometer type, with frame made of aluminum alloy, digit drums are made of polycarbonate, UV radiation resistant, the register is fixed on the meter frame by two screws it is adjustable to assure good mesh of worm with the rotor shaft
Unidirectional register is available
7, name plate
Printing ink used for name plate is UV radiation resistant one
Technology data
1.current   3(9)A 5(15)A  10(30)A 15(45)A 5(20)A  10(40)A  20(80)A 30(100)A
2.over load capacity  300%  400%
3.voltage 110V 120V  220V 230V  240V
4.frequency  50Hz  60Hz
5.power loss in voltage circuit  1.3W/6VA 50Hz   1.1W/5.5VA 60Hz
6.power loss in current circuit  less than 0.6VA
7.running with no load 0.8-1.1Un
8.starting current 0.5% Ib
9.AC voltage test 50Hz 1min    2KV
10.Impulse voltage test 1.2/50Us  6KV