LC1D38U7

What type of device is this used for in control panels?

It is an IEC power contactor designed to switch electrical power to loads such as motors and resistive heaters from a control circuit. It provides three main normally-open power poles for switching a three-phase circuit.

What are the main electrical ratings for the power circuit?

The power circuit is rated up to 690 V AC (25–400 Hz) and up to 300 V DC. Typical operational current ratings include 38 A for AC-3 motor duty (up to 440 V AC) and 50 A for AC-1 resistive duty (up to 440 V AC), at up to 60 °C ambient.

What coil voltage does it require?

It uses a 240 V AC coil (50/60 Hz). In practice this suits common UK control voltages such as 230–240 V AC.

Does it include auxiliary contacts for control signalling?

Yes. It includes built-in auxiliary contacts: 1 normally open (NO) and 1 normally closed (NC), suitable for interlocking, status feedback, and control logic.

Is the auxiliary NC suitable for mirror contact applications?

The built-in auxiliary NC is specified as a mirror contact type to IEC 60947-4-1, which is commonly used where a positively guided indication of main contact position is required.

What motor sizes is it commonly used with?

Typical motor power ratings include 9 kW at 220–230 V AC (AC-3) and up to 18.5 kW at 380–440 V AC (AC-3), with higher ratings shown for 500 V and 690 V systems depending on duty. Always confirm against the motor full-load current and the utilisation category.

What utilisation categories does it cover and why does that matter?

It is specified for AC-1 (resistive loads), AC-3 / AC-3e (squirrel-cage motor starting and running), and AC-4 (more severe inching/jogging and plugging duties). Selecting the correct category ensures the contactor is sized for the switching stress of your application.

How is it typically mounted in an enclosure?

It supports both DIN rail and panel mounting (plate mounting), making it suitable for standard industrial control cabinets and motor starter assemblies.

What degree of protection does it have?

It has an IP20 rating on the front face, meaning it is intended for installation inside an enclosure where additional protection against accidental contact and ingress is provided.

What are the approximate dimensions and weight for cabinet planning?

Typical overall dimensions are about 85 mm (H) × 45 mm (W) × 92 mm (D), with a net weight of approximately 0.38 kg. This helps with rail spacing and thermal layout in compact panels.

What conductor sizes can be used on the terminals?

The control terminals accept conductors in the 1–4 mm² range (with some configurations supporting 1–2.5 mm² with ferrules). The power terminals accept a range up to 10 mm² depending on conductor type (solid/flexible and whether ferrules are used).

What tightening torques should be used on the terminals?

Typical tightening torques are 1.7 N·m for the control terminals and 2.5 N·m for the power terminals. Using the correct torque helps maintain reliable connections and reduces the risk of overheating.

Does the coil include a built-in surge suppressor?

No. The coil is specified without a built-in suppressor module. If suppression is required for your control circuit (for example, to reduce electrical noise), it is typically added externally.

What are the coil power requirements?

The coil inrush is specified at about 70 VA at 50/60 Hz, and the hold-in consumption is about 7 VA (50 Hz) or 7.5 VA (60 Hz). These values are useful when sizing control transformers and PLC output relays.

What temperature range can it operate in?

Typical permissible ambient temperature around the device is -40 to +60 °C, with derating up to +70 °C. This makes it suitable for a wide range of industrial cabinet environments when appropriately ventilated.

Is it suitable for DC switching on the power poles?

The power circuit is rated for use up to 300 V DC. For DC applications, ensure the load current, switching frequency, and any required protection are suitable for the specific DC duty.

What standards is it designed to comply with?

It is designed in line with key industrial contactor standards, including IEC 60947-4-1 and UL 508, supporting use in a wide range of industrial control panel designs. The LC1D38U7 variant is commonly specified where these approvals are required.