(2) Functions

(a) Data collection and control: high speed direct sampling and effective value calculation of AC voltages and currents, calculation of active power/reactive power/power factor, collection and transmission of states, select-check-execute of control output;

(b) Fault detection: detection and indication of inter-phase and earthed phase fault, detection of broken wire, transmission of fault data, fault isolation and service restoration.

(c) Statistics: average load statistics, daily maximum load statistics, breaker operation and life statistics, service reliability statistics, reset statistics, etc.

(d) Backup power source management: battery charging and discharging management ( including detection of battery terminal voltage, battery capacity, battery performance ), auto backup switch-on when main power source disappears

(e) Prevention of misoperation and blocking: blocking of misphase/low pressure of gas/abnormal operation mechanism

(f) Message relay

(3) Types
(a) DEP-910 - pole top FTU
(b) DEP-930 - switchgear DTU
(c) DEP-990 - distribution transformer TTU

(4) Specification
AC voltage input: 0~120 V
AC current input: 0~40 A or 0~20A, optional
Sample accuracy for current/voltage: 0.2%
Sample accuracy for active power/reactive power: 0.5%
Sample accuracy for frequency: ≤0.01HZ

(5) Mechanical stress tests, vibration, shock stress and seismic vibration
IEC60255-21-1, Class II
IEC60068-2-6

(6) EMC tests
IEC60255-22-1 HF Disturbance Test with Damped Oscillatory Wave, Class III (2.5KV c.m. 1KV d.m.)
IEC60255-22-2 Electrostatic Discharge Disturbance Tests, Level IV
IEC60255-22-3 Radiated Electromagnetic Field Disturbance Tests, Class III
IEC60255-22-4 Fast Transient Disturbance Tests, Class III