D4NL-4EFG-B

What does this component do in a machine guarding system?

It is a guard-lock, key-operated door switch with an integrated solenoid lock. When used with a compatible operation key, it monitors guard/door position and provides a lock status signal, while also physically locking the guard when the solenoid is energised.

Is it power-to-lock or power-to-unlock?

It is power-to-lock (solenoid lock). The guard is locked only when 24 VDC is applied to the solenoid; if solenoid power is removed, the lock is released.

What is the solenoid voltage requirement?

The solenoid is rated for 24 VDC.

Does the 24 VDC solenoid have polarity?

Yes. The 24 VDC solenoid is polarised, so the solenoid terminals must be wired with the correct polarity for proper operation.

What contact configuration is provided for door monitoring and lock monitoring?

It provides two door (guard open/closed) NC contacts and one door NO contact, plus one lock monitor NC contact and one lock monitor NO contact (slow-action contacts).

Does it include an indicator, and how is it typically wired?

Yes, it includes an orange LED indicator. It is typically connected in parallel with auxiliary circuits (or via the dedicated indicator terminals) rather than across direct-opening circuits.

What is the holding force of the guard lock?

The minimum specified holding force is 1,300 N.

What is the enclosure protection rating?

The switch body is rated IP67 when correctly installed. Note that the key insertion opening is not sealed to the same level (the key hole is rated IP00).

What are the operating temperature limits?

The specified operating ambient temperature range is -10°C to +55°C (non-icing).

How is this unit connected (cable or terminals)?

It uses a terminal block connection method (no fixed cable). Suitable lead wire size is typically AWG20 to AWG18 (0.5 to 0.75 mm²), and crimp terminals should be selected to fit the terminal hardware and internal clearances.

What conduit entry does it have?

It has M20 conduit entries and provides two conduit openings (commonly used as horizontal and vertical entries). Unused openings should be sealed with the supplied cap to maintain ingress protection.

Can the head/orientation be changed during installation?

Yes. The direction of operation is adjustable and the head can be mounted in multiple directions, allowing flexible alignment with the operation key. Follow correct procedures when changing head direction to avoid internal damage or misoperation.

Which operation keys are compatible?

It uses a separate operation key (sold separately). Common compatible key types include the D4DS series operation keys (for example, horizontal, vertical, and adjustable key styles).

When is a solenoid-lock type not suitable?

Because the lock releases if solenoid power is removed, it should only be used where unlocking on power loss is acceptable for the application and risk assessment. If you need a lock that remains locked during a power interruption, a mechanical-lock variant is typically selected instead.