Electronic Three-phase Four-wire Energy Meter (CT Input), Three-phase Three-wire Energy Meter (CT Input) and Three-phase Four-wire Energy Meter (Direct Input) adopt the latest micro-electronic technology to measure three-phase AC active power energy with frequency 50/60Hz,meanwhile fulfill prepayment management function which means paying the expenses firstly, consuming energy afterwards as well as load control function. This series of watt-hour meter has special outside structure and exclusive function features which can suit for different requirements for power consuming. Function: Overdraft can be permitted once under emergency condition, the overdraft amount=Load Gate x 24 Hours. When meter trips at overload or the energy is exhausted, signal will be sent out for external warning facilities to remind customer of purchasing power or reducing load used. Load control can be selected. (1) Delaying trip at overload and the delay time can be selected freely (2) No trip at overload but measuring overload energy separately Applicable condition: Working at an ambient temperature -25 ℃ ~ +65 ℃, relative humidity of 85% of the environment Maximum Demand Clear Max Demand can be cleaned by use of Data Collected Card. Overdraft Function The selection to the energy overdraft function can be processed according to the requirementof user to realize the overdraft function once when residual energy is less than the warning gate. If no selection, the meter will take as no overdraft. Pre-warning Output Function By Means of Trip To make the meter's warning function more effective in reminding user, this meter adds an output return circuit with no battery contacts (AC 220V x 5A/DC 12V x 12A) to realize the output of (1) warning at overload (2) pre-warning at energy deficiency Types And Norms (Types And Names)/Norm Accuracy Class Rated Voltage (V) Nominal Current (A) DTSY26 Model Electronic Three-phase Four-wire Prepayment Watt-hour Meter (CT Input) 1.0 3x220(380) 3x1.5(6) DSSY27Model Electronic Three-phase Three-wire Prepayment Watt-hour Meter (CT Input) 1.0 3x100 3x1.5(6) DSSY26 Model Electronic Three-phase Three-wire Prepayment Watt-hour Meter (CT Input) 0.5 3x100 3x1.5(6) DTSY23 Model Electronic Three-phase Four-wire Prepayment Watt-hour Meter (Direct Input) 1.0 3x220(380) 3x5(30) 3x10(60) Technical Specifications Power Consumption: every voltage circuit<1.0W every current circuit<1.0VA Outside Size:285mmx176mmx86mm Weight:<=3 Kg Star Current: DTSY26/DSSY27/DSSY26 0.2%In DTSY23 0.4%Ib Display Bit Data:7digits include 2 decimals. Latent Running: there is anti-latent running logical circuit Ambient Temperature:-30'C-65'C Relative Humidity:<=85% Meter Constant: DTSY26 1600imp/kW.h DSSY27/DSSY26 3200imp/kW.h DTSY23-5(30)A 300imp/kW.h DTSY23-10(60)A 200imp/kW.h Voltage Scope: Three-phase Four-wire Meter: Rated Operation Scope: 175V-250V Max Operation scope:150V-275V; Three-phase Three-wire Meter: Rated Operation Scope: 80V-150V Max Operation scope: 70V-125V; Capacity of No Battery Output Contacts: Tripping Return Circuit: AC 277V 5A/DC 30V 5A; Warning Return Circuit: AC 277V 2A/DC 30V 5A.