TXCM1Z Molded Case Circuit Breaker (16A~250A, 225A~400 amp or 400 amp~ 630A DC Circuit Breaker, PV DC MCCB) is used for low-voltage power generation, transmission and distribution lines of rated voltage of DC500V, 750V and 1000V, rated current of 16A~250A, 225A~400 amp or 400 amp~ 630A to provide isolation, overload and short circuit protection, DC MCCB can also be used for infrequent making and breaking of circuits under normal circumstances.
The DC MCCB are widely used in photovoltaic power generation systems, wind power generation systems, roof building power generation systems, rail transit power distribution systems and infrastructure construction and other low-voltage DC generation, transmission and distribution application occasions.

Two release methods

Thermal + electromagnetic release

● Altitude of TXCM1Z DC MCCB installation place in normal work is not more than 2000m.
● If you need to install it at an altitude of more than 2000m, which can be used according to the altitude factor derating table.

Derating factor of altitude corresponds to the circuit breaker

● Can be used in the lowest temperature of -25℃, the highest temperature of +40℃.
● If they need to work at less than -25℃ or higher than +40℃, you can use them according to temperature compensation factor table.
● Consult with the manufacturer when using at less than -25℃ or more than +40℃.

Ambient temperature changes in the temperature compensation factor table

● In the ambient air temperature of +40℃, atmospheric relative humidity can not exceed 50%, if the temperature is low, you can use it under high humidity conditions.
● The monthly average relative humidity of the wettest month is 90%, and the effect of condensation on the product surface should be considered.

● Level 3

Time / current characteristic curve of TXCM1Z-250

Time / current characteristic curve of TXCM1Z-400(including 400 amp DC Circuit Breaker)

Time / current characteristic curve of TXCM1Z-630(including 400 amp DC Circuit Breaker)

Wiring mode of circuit breaker in different voltage and different DC system

Different power system / load wiring mode

Note: (1) In the negative grounded system, the wiring must be according to the above table.
(2) In the ungrounded system and the neutral point grounded system, use the wiring on the table. User page
can exchange the positive and negative based on the actual situation, but also can exchange wiring position
of the power supply and load.

DC system applications

Choosing circuit breakers in a DC system need to mainly consider the following aspects:
● Rated operating voltage, consider the breaking poles in series
● Rated current, consider the load power
● Breaking capacity, consider the max short-circuit current at the installation point

Front plate wiring of TXCM1Z-250 3-pole (mm)

Front plate wiring of TXCM1Z-250 4-pole (mm)

Front plate wiring of TXCM1Z-400 3-pole (mm)

Front plate wiring of TXCM1Z-400 4-pole (mm)

Front plate wiring of TXCM1Z-630 3-pole (mm)

Front plate wiring of TXCM1Z-630 4-pole (mm)

Type / Installation location / Poles / Accessory name	TXCM1Z-250		TXCM1Z-400		TXCM1Z-630
	3P	4P	3P	4P	3P	4P
Nothing	-		-		-
Shunt release
Auxiliary contact
Undervoltage release
Shunt release Auxiliary contact
Shunt release Undervoltage release
Two sets of auxiliary contact
Undervoltage release Auxiliary contact Auxiliary contact
Alarm contact
Shunt release Alarm contact
Auxiliary contact Alarm contact
Undervoltage release Alarm contact
Shunt release Auxiliary+Alarm contact
Two sets of auxiliary contact Alarm contact
Undervoltage release Auxiliary+Alarm contact

The cross-sectional area of the TXCM1Z connecting wire and the corresponding rated current

TXCM1Z 250 H P 3R 300

Keywords: DC MCCB,400 amp dc Circuit Breaker