Scope for AC 50 / 60Hz, 400V emergency power supply system. When one power supply fails, the auto-complete between the common power supply and standby power switch, without human intervention, to protect important user power supply reliability. Mainly used in hospitals, shopping malls, banks, chemical industry, metallurgy, high-rise building and fire and other important places are not allowed off. This product complies with IEC60947-6-1 "Automatic Transfer Switching Equipment" standard. Model and its meaning NZ7-400S / 4-350-2-ARX NZ7- dual power automatic transfer switch (NM1 MCCB) 400- MCCB frame degree current [63,100,225,400,630, 800A] S- breaking capacity code, S, H, R 4- molded case circuit breaker poles (3-pole, 4-pole) 350- Y- rated current dual power structure, Y: one type is not marked, split, A- Controller category, A: basic, B: LCD type R- conversion modes: automatic recovery (R, grid - grid), since the vote of no self-recovery (S grid - grid), and automatic recovery (F grid - generator) X- fire function, without nowadays do not mark the time of order; terminal type meaning NZ7B-63 □ / ■ NZ7B-DZ47 terminal type [type] dual power automatic transfer switch 63- frame degree rated current □ - breaking level Symbol, S [Executive miniature circuit breakers DZ47-60, C-type, rated current ≤40A], H [Executive miniature circuit breakers NB1-63H, C / D type] ■ - poles, around 3,4 normal operating conditions the air temperature : -10 ~ + 40 ℃, 24h average does not exceed + 35 ℃; the installation site altitude does not exceed 2000m; atmospheric conditions: relative humidity less than 85%. Mode automatic operation mode [automatic recovery, Grid - Grid (R)] for common / standby power monitoring and automatic switching, when two power supplies are working properly by a common power supply, an exception occurs when the normal power supply (any one phase overvoltage, undervoltage, phase), the switch automatically switches to standby power, commonly used to restore the normal power supply is switched automatically and immediately received a common power supply. [Since the vote of no self-recovery, Grid - Grid (S)] of the common power supply / backup power monitoring and automatic switching. When the normal power supply is abnormal, the switch automatically switches to backup power when the normal power supply back to normal does not switch to the common power until the backup power anomalies, and then automatically change to the common power supply. [Automatic recovery, power - generator (F)] applies to the first two grid - grid power systems, the latter adapted to the grid - generator system. Manual mode common power supply, standby power and circuit breakers and subtract three operating modes. In manual mode the system will not automatically switch function. [Common power supply] forcibly remove standby power mode, turn common power. [] Forced off standby power mode common power, standby power is turned on. [Mode] button again to power the two-way power all off, but also make the trip due to failure of the circuit breaker and then buckle. ① with fire control circuit, when the fire control center to a control signal into the intelligent controller, two circuit breakers into the sub-gate status, and to the fire control center an acknowledgment signal; ② with function generator start signal, when common abnormal power ATS controller will send a signal to start the generator