About the BY4 Surge Arrestor

The BY4 Surge Arrestor is part of the ELEHPD Surge Arrester range. BY4 Surge protective device BY4-60/3P BY4-80/3P Specification Type Pole Uc (V) In(kA) Imax(kA) Up(kV) BY4-60/3-320 3 320 30 60 2.0 BY4-80/3-320 3 320 40 80 2.0 BY4-100/3-320 3 320 60 100 2.5 BY4-60/3N-320 3 320 30 60 2.0 BY4-80/3N-320 3 320 40 80 2.0 BY4-100/3N-320 3 320 60 100 2.5 BY4-60/4-320 4 320 30 60 2.0 BY4-80/4-320 4 320 40 80 2.0 BY4-100/4-320 4 320 60 100 2.5 BY4-60/3N-385 3 385 30 60 2. ELEHPD manufactures and exports low voltage electrical products from Yueqing, Zhejiang, China, supplying distributors, panel builders, M&E contractors and OEM buyers worldwide.

Typical applications

Consumer units and distribution boards in residential buildings
Commercial and retail fit-outs where selective protection is required
Industrial control panels and machine-builder assemblies
Solar PV, EV charger and battery-storage sub-circuits
OEM equipment where a DIN-rail protective device is specified

How to specify the right Surge Arrester

Match the rated current to the circuit design current, then check the cable ampacity
Pick the trip curve to the load: B for resistive/lighting, C for general mixed loads, D for motors and transformers
Confirm the breaking capacity meets the prospective short-circuit current at the point of installation
Verify the pole configuration (1P, 1P+N, 2P, 3P, 3P+N, 4P) against the system earthing arrangement

Specifications

BY4 Surge protective device

Q: What is the difference between an MCB and an MCCB?

An MCB (miniature circuit breaker) is a DIN-rail device for final circuits, typically rated up to 125 A with a fixed trip curve. An MCCB (moulded case circuit breaker) is a larger device for main and sub-main distribution, usually 16 A to 1600 A, with adjustable thermal and magnetic settings and a higher breaking capacity. Use an MCB for branch circuits and an MCCB where you need adjustability or higher fault ratings.

Q: How do I choose between a Type B, C and D trip curve?

Type B trips between 3 and 5 times rated current and suits resistive loads such as lighting and heaters. Type C trips between 5 and 10 times and is the general-purpose choice for socket circuits and mixed loads. Type D trips between 10 and 20 times and is used for loads with high inrush, such as motors, transformers and large LED drivers.

Q: What does 6 kA breaking capacity mean in practice?

It is the maximum prospective short-circuit current the device can safely interrupt. 6 kA covers most domestic and light commercial installations. Where the transformer is close and the fault level is higher, specify 10 kA devices so the breaker still clears the fault without damage.

Q: Can these devices be supplied with your own brand?

Yes. OEM branding, buyer-specific labels, custom carton print and private-model numbering can be arranged on qualified order volumes.

BY4-60/3P

BY4-80/3P

Specification

Type	Pole	Uc (V)	In(kA)	Imax(kA)	Up(kV)
BY4-60/3-320	3	320	30	60	2.0
BY4-80/3-320	3	320	40	80	2.0
BY4-100/3-320	3	320	60	100	2.5
BY4-60/3N-320	3	320	30	60	2.0
BY4-80/3N-320	3	320	40	80	2.0
BY4-100/3N-320	3	320	60	100	2.5
BY4-60/4-320	4	320	30	60	2.0
BY4-80/4-320	4	320	40	80	2.0
BY4-100/4-320	4	320	60	100	2.5
BY4-60/3N-385	3	385	30	60	2.0
BY4-60/3N-385	3	385	40	80	2.5
BY4-60/3N-385	3	385	60	100	3.0
BY4-60/4-385	4	385	30	60	2.0
BY4-80/4-385	4	385	40	80	2.5
BY4-100/4-385	4	385	60	100	3.0

Notes: Some of these types are available with accessories: alarm and remote signalling contact ( those ending with B and X ).

Technical Parameters :

	BY4-60/3-385 BY4-60/3N-385 BY4-60/4-385	BY4-80/3-385 BY4-80/3N-385 BY4-80/4-385	BY4-100/3-385 BY4-100/3N-385 BY4-100/4-385
Maximum continuous operating voltage Uc	385 V
Test grade	Class 2
Nominal discharge current In(8/20 µ s) kA	30 kA	40 kA	60 kA
Maximum discharge current Imax (8/20 µ s) kA	60 kA	80 kA	100 kA
Voltage protective level Up	2.0 kV	2.5 kV	3.0 kV
Response time ns	< 25 ns
Defending grade	IP20
Ambient temperature	-40---- +85 ℃
Color ( Mould )	Orange
( Base )	Grey
Outer covering material	Reinforced fire-retardant nylon PBT
Phase Line , Zero Line	6 ----3 5 mm ²
Earth Line	6 ----3 5 mm ²
Signal Line	1.5 mm ²
Accessory	According to the needs adding the remote signaling contact

	BY4-60/3-320 BY4-60/3N-320 BY4-60/4-320	BY4-80/3-320 BY4-80/3N-320 BY4-80/4-320	BY4-100/3-320 BY4-100/3N-320 BY4-100/4-320
Maximum continuous operating voltage Uc	320 V
Test grade	Class 2
Nominal discharge current In(8/20 µ s) kA	30 kA	40 kA	60 kA
Maximum discharge current Imax (8/20 µ s) kA	60 kA	80 kA	100 kA
Voltage protective level Up	2.0 kV	2.0 kV	2.5 kV
Response time ns	< 25 ns
Defending grade	IP20
Ambient temperature	-40---- +80 ℃
Color ( Mould )	Orange
( Base )	Grey
Outer covering material	Reinforced fire-retardant nylon PBT
Phase Line , Zero Line	6 ----3 5 mm ²
Earth Line	6 ----3 5 mm ²
Signal Line	1.5 mm ²
Accessory	According to the needs adding the remote signaling contact

Appearance and Installation Dimension

Operating Principle

In three-phase four- line system , three phase lines and one zero line are connected protective device to the earth cable . (figure 9 ) . In normal situation , the protective device is high resistance , when the over voltage brings for electric network shocked by thunder or other reasons , the protective device will rapidly transmit in ns , then lead the voltage into earth and protect the electric equipment . As the surge voltage through the protective device and after disappear it will recover to high resistance and not influence the normal operating . Figure 10 is the electric principle about it.

Installation Location and Application

SPD class D, functioning as an equi-potential connection in case of lightning.

Installed at the joint of the LPZOA, LZPOB and LPZ1 zones.

It is usually installed in low voltage main distribution cabinet connected to the incoming end of the buildings.

It adopts 35 mm DIN rail.

It is linked by 6 --- 35 mm² copper wire.

The cable should choose double color wire which is longer than 6 mm ² .

In order to guarantee electrical network's normal operating after protective device losing efficiency , the protective device which linked to the phase line must be connected a fuse box whose current is higher than 63A or a circuit breaker.

Frequently asked questions about the BY4 Surge Arrestor

What is the difference between an MCB and an MCCB?

An MCB (miniature circuit breaker) is a DIN-rail device for final circuits, typically rated up to 125 A with a fixed trip curve. An MCCB (moulded case circuit breaker) is a larger device for main and sub-main distribution, usually 16 A to 1600 A, with adjustable thermal and magnetic settings and a higher breaking capacity. Use an MCB for branch circuits and an MCCB where you need adjustability or higher fault ratings.

How do I choose between a Type B, C and D trip curve?

Type B trips between 3 and 5 times rated current and suits resistive loads such as lighting and heaters. Type C trips between 5 and 10 times and is the general-purpose choice for socket circuits and mixed loads. Type D trips between 10 and 20 times and is used for loads with high inrush, such as motors, transformers and large LED drivers.

What does 6 kA breaking capacity mean in practice?

It is the maximum prospective short-circuit current the device can safely interrupt. 6 kA covers most domestic and light commercial installations. Where the transformer is close and the fault level is higher, specify 10 kA devices so the breaker still clears the fault without damage.

Can these devices be supplied with your own brand?

Yes. OEM branding, buyer-specific labels, custom carton print and private-model numbering can be arranged on qualified order volumes.