YCB8-125PV Photovoltaic DC MCB

Features

● Modular design, small size; ● Standard Din rail installation, convenient installation; ● Overload, short circuit, isolation protection function, comprehensive protection; ● Current up to 125A, 4 options; ● The breaking capacity reaches 6KA, with strong protection capacity; ● Complete accessories and strong expansibility; ● Multiple wiring methods to meet various wiring needs of customers; ● The electrical life reaches 10000 times, which is suitable for the 25-year life cycle of photovoltaic.

Selection

YCB8	—	125	PV	4P	63	DC250	+	YCB8-63 OF
Model		Shell grade current	Usage	Number of poles	Rated  current	Rated  voltage		Accessories
Miniature circuit breaker		125	Photovoltaic/ direct-current PV: heteropolarity Pvn: nonpolarity	1P	63A, 80A, 100A, 125A	DC250V		YCB8-125 OF: Auxiliary
				2P		DC500V		YCB8-125 SD: Alarm
				3P		DC750V		YCB8-125 MX: Shunt
				4P		DC1000V

Note: The rated voltage is affected by the number of poles and wiring mode. The single poleis DC250V, the two poles in series are DC500V, and so on.

Technical data

Standard		IEC/EN 60947-2
Number of poles		1P	2P	3P	4P
Rated current of shell frame grade		125
Electrical performance
Rated working voltage Ue(V DC)		250	500	750	1000
Rated current In(A)		63、80、100、125
Rated insulation voltage Ui(V DC)		500VDC per pole
Rated impulse voltage Uimp(KV)		6
Ultimate breaking capacity Icu(kA)		Pv：6 PVn：10
Operation breaking capacity Ics(KA)		PV：Ics=100%Icu  PVn：Ics=75%Icu
Curve type		li=10ln(default)
Tripping type		Thermomagnetic
Service life (time)	Mechanical	20000
	Electrical	PV：1000  PVn：300
Polarity		Heteropolarity
Inline methods		Can be up and down into the line
Electrical accessories
Auxiliary contact		□
Alarm contact		□
Shunt release		□
Applicable environmental conditions and installation
Working temperature(℃)		-35~+70
Storage temperature(℃)		-40~+85
Moisture resistance		Category 2
Altitude(m)		Use with derating above 2000m
Pollution degree		Level 3
Protection degree		IP20
Installation environment		Places without significant vibration and impact
Installation category		Category III
Installation method		DIN35 standard rail
Wiring capacity		2.5-50mm²
Terminal torque		3.5N·m

■ Standard   □ Optional   ─ No

Wiring diagram

Overall and mounting dimensions(mm)

Tripping characteristics

Circuit breaker under normal installation conditions and reference ambient temperature (30~35)℃

Tripping type	DC current	Initial state	Appointed time	Expected results
All types	1.05In	Cold state	t≤2h	No tripping
	1.3In	Thermal state	t<2h	Tripping
Ii=10In	8In	Cold state	t≤0.2s	No tripping
	12In		t<0.2s	Tripping

Curve

Temperature correction factor table

Current correction value for different ambient temperatures

Temperature (℃) Rated current (A)	-25	-20	-10	0	10	20	30	40	50	60
63A	77.4	76.2	73.8	71.2	68.6	65.8	63	60	56.8	53.4
80A	97	95.5	92.7	89.7	86.6	83.3	80	76.5	72.8	68.9
100A	124.4	120.7	116.8	112.8	108.8	104.5	100	95.3	90.4	87.8
125A	157	152.2	147.2	141.9	136.5	130.8	125	118.8	112.3	105.4

Use of derating table at high altitude

Current correction factor at different altitudes

Rated current(A)	Current correction factor
	≤2000m	2000-3000m	≥3000m
63, 80, 100, 125	1	0.9	0.8

Example: If a circuit breaker with a rated current of 100A is used at an altitude of 2500m, the rated current must bederated to 100A×90%=90A

Power consumption per pole of circuit breaker and wiring size

Rated current In(A)	Nominal cross-section of copper conductor(mm²)	Maximum power consumption per pole(W)
63	16	13
80	25	15
100	35	15
125	50	20

Accessories

The following accessories are compatible with the YCB8-125PV series circuit breakers. They enable functions such as remote operation, automatic fault circuit disconnection, and status indication (open/closed/fault trip).

Key Features

a. The total combined width of the accessories is no more than 54mm. They can be arranged in the following sequence (from left to right): OF, SD (up to 3 pieces max) + MX, MX + OF, MV + MN, MV (up to 1 piece max) + MCB. Note that a maximum of 2 SD units can be assembled. b. Accessories are easily assembled onto the main body without requiring tools. c. Before installation, verify that the product’s specifications meet usage requirements. Test the mechanism by operating the handle to open and close a few times, ensuring reliable performance.

Accessory Functions

● Auxiliary Contact (OF): Provides remote signaling of the circuit breaker’s open/closed status. ● Alarm Contact (SD): Sends a signal when the circuit breaker trips due to a fault, accompanied by a red indicator on the device’s front panel. ● Shunt Release (MX): Enables remote tripping of the circuit breaker when the supply voltage is within 70%-110% of Ue. ● Minimum operational current: 5mA (DC24V). ● Service life: 6,000 operations (1-second intervals).

Technical data

Model	YCB8-125 OF	YCB8-125 SD	YCB8-125 MX
Appearance
Types
Number of contacts	1NO+1NC	1NO+1NC	/
Control voltage (V AC)			110-415 48 12-24
Control voltage(V DC)			110-415 48 12-24
Working current of contact	AC-12 Ue/Ie: AC415/3A DC-12 Ue/Ie: DC125/2A		/
Shunt control voltage			Ue/Ie: AC:220-415/ 0.5A AC/DC:24-48/3
Width(mm)	9	9	18
Applicable Environmental Conditions and Installation
Storage temperature(℃)	-40℃~+70℃
Storage humidity	the relative humidity does not exceed 95% when at +25℃
Protection degree	Level 2
Protection degree	IP20
Installation environment	Places without significant vibration and impact
Installation category	Category II 、Category III
Installation method	TH35-7.5/DIN35 rail installation
Maximum wiring capacity	2.5mm²
Terminal torque	1N·m

Overall and mounting dimensions(mm)

Alarm Contact Outline and installation dimensions MX+OF Outline and installation dimensions MX Outline and installation dimensions