Phoenix Contact UT 4-PE Protective Earth Terminal Block

UT 4-PE: protective earth terminal for 4 mm² conductors

The UT 4-PE is the protective earth version of the UT 4 and carries a green-yellow housing so that it can be recognised on sight. A metal foot at the bottom makes a conductive connection to the mounting rail when it is clicked on, which links all earth conductors in the row to the rail and then to the cabinet earth.

Order number 3044128 has two screw connections, a nominal cross section of 4 mm² and follows IEC 60947-7-2, the standard for protective conductor terminal blocks. The product page also lists an Ex marking. Seven Star LLC supplies the UT 4-PE in Oman and the GCC as an independent supplier in Muscat.

Technical specifications of the UT 4-PE

How the UT 4-PE earths a conductor to the rail

A protective earth terminal is not designed to carry load current but to hold a safety conductor reliably and to keep a low-resistance path to the rail. The grounding foot presses against the DIN rail, so earth from every field cable on the row ends up at one common potential. Because the contact is made through the rail, the rail itself must be well connected to the cabinet earth bar with a proper conductor.

The screw clamp is M3 with torque 0.6 to 0.8 Nm. It takes 0.14 to 6 mm² rigid conductors; for flexible conductors the Ex data lists up to 4 mm². Do not use the PE block for circuits that carry operational current.

Where the UT 4-PE fits in a terminal row

Place UT 4-PE blocks in the same row as UT 4 feed-through blocks so that the earth of each cable can be terminated beside its phase or signal conductors. Because the housing is green-yellow, inspectors and maintenance staff see the earth connection at once.

The UT 4-PE is for 4 mm² wiring. For larger conductors the UT 6-PE and UT 10-PE share the same concept, and the UT 10-PE is covered by a separate page in this series.

Selection and ordering checklist for the UT 4-PE

• Conductor size: up to 6 mm² rigid.
• Check that the rail used is earthed and conductive.
• Hazardous-area use: the page lists a marking of II 2 GD Ex eb IIC Gb; confirm certificates for your project.
• Temperature range of -60 to 110 °C against site needs.
• Need for end covers and the accessory listed (3047028 D-UT 2,5/10).
• Quantity in packing units.

Installation, commissioning and maintenance of the UT 4-PE

Mount on a rail that is cleaned of paint at the contact points; the foot must touch bare metal. Terminate the earth conductor with a ferrule, tighten the screw to 0.6 to 0.8 Nm and check continuity from the conductor end to the earth bar.

In an Ex e enclosure, follow the certificate conditions and use only the accessories listed on the product page. Verify earth continuity as part of regular inspection and record the result.

Typical applications in Oman and the GCC

In Oman and the GCC the UT 4-PE is used in instrument junction boxes, control panels on gas plants, and enclosures in classified areas. Earth integrity is critical where static discharge or fault currents are a risk, so the correct terminal and a well-bonded rail are essential.

In very hot sites, the wide operating temperature range printed on the product page is a useful check for outdoor panels.

Practical design notes for the UT 4-PE

Protective earth terminals follow different rules from power terminals, and the UT 4-PE is no exception. Its job is to give a dependable, low-resistance path for fault current and for bonding, not to carry operating current. A clean, bare-metal contact between the grounding foot and the rail is the single most important installation detail, followed by a properly sized bonding conductor from the rail to the earth bar.

When you plan a panel, place one PE block near each group of circuits so that cable armour, screens and equipment earths do not have to run far. Mark the blocks clearly, keep the green-yellow colour consistent for earth only, and do not stack other functions on the same terminal. If your project requires periodic earth testing, leave an access point on the earth bar for the test lead.

Comparison with neighbouring UT sizes

Information to send with an RFQ for the UT 4-PE

• Full part number UT 4-PE and quantity in pieces (the page lists a packing unit of 50).
• Ex area requirement and zone.
• Rail and earth bar arrangement.

Documents and quotation

Send us the part number UT 4-PE and the quantity you need, and we will confirm which official documents are available for this item. Seven Star LLC is an independent supplier in Muscat and quotes for projects across Oman and the GCC; we do not act on behalf of the manufacturer.

Please also tell us the delivery location and the project timeline so that availability can be checked before you commit to a schedule.