SINAMICS SIRIUS series switchgear

Select relay module: PT type 3 conversion contact (LZX: PT370024, 24V DC);

Select base: Spring terminal base with logic separation (LZS: PT7874P);

Select LED module: green with freewheeling diode (LZS: PTMG0024);

Select protective component: RC component (LZS: PTMU0524, 24~60V AC).

Core accessories:

Accessory type, model, example, function description, adaptation type, corresponding page number

LED module (red) LZS: PTML0024 24V DC, with freewheeling diode, indicating relay status PT type 5/42

Fixed/pop-up bracket LZS: PT17021 auxiliary disassembly relay, suitable for dense installation of PT type 5/42

RC component LZS: PTMU0524 suppresses coil surge, 24~60V AC PT/MT/RT type 5/42

Connect comb LZS: PT170R6 (6-pole) to the same potential terminal, current capacity 10A PT type 5/42

General Technical Specifications and Safety Standards

At the end of the document, the universal connection methods, security features, and standard certifications for the entire series of products were added to ensure the compliance and security of technical applications.

1. Connection method (universal across the entire series)

Screw terminal: requires tool fastening, wire section 0.5~4mm ² (solid/multi strand with end sleeve), torque 0.8~1.2Nm (3RH2), 0.6~0.8Nm (3RQ2), suitable for large section wires and low vibration scenarios;

Spring terminal (push in):

Advantages: Tool free wiring (hard wire/soft wire with end sleeve), requires a 3.0 × 0.5mm screwdriver for wire removal, earthquake resistant (no risk of loosening), and does not require regular torque checks;

Wire cross-section: 0.5~4mm ² (solid), 0.5~2.5mm ² (multi strand with/without end sleeve);

Plug in terminal: Only supported by LZS series, suitable for scenarios that require frequent replacement of relays, with a wire cross-section of 0.75~1.5mm ².

2. Safety features and standard certification

Core standards:

IEC/EN 60947-1: General Standard for Low Voltage Switchgear;

IEC/EN 60947-4-1: Standard for contactors and motor starters;

IEC/EN 60947-5-1: Electrical standard for control circuits (including requirements for mandatory guide contacts);

IEC 60529: Standard for Degrees of Protection Provided by Enclosures (IP20/IP00/IP50).

Security features:

Finger protection: The front meets IP20 standards to prevent fingers from coming into contact with live parts;

Mandatory guiding contact: 3RH2 and 3TH4 series basic units are equipped to ensure that NO/NC contacts do not close simultaneously (essential for safe applications);

Short circuit protection: Suitable for G-type fuses (such as 3NA, 5SB) or C/B characteristic miniature circuit breakers, with a short-circuit current of 1kA (IEC 60947-5-1).

3. General requirements for installation and maintenance

Installation position: Vertical installation (base facing up), when installing 3TH4 series AC type on the side, a 5mm gap should be left (to prevent overheating);

Wiring specification: Separate the wiring of coils and contact circuits to avoid electromagnetic interference;

Maintenance cycle: Check the terminal fastening status (screw terminals) and contact wear every 6 months (measured by LED indicator or multimeter).

Summary and Core Values

This document serves as the authoritative technical manual for Siemens SIRIUS series switchgear, with core values reflected in:

Technical integrity: covering the entire series of contactor relays and coupling relays, with detailed parameters (including size, current, and lifespan), clear selection logic, and can directly guide engineering design;

Targeted application: classified according to "compact → multipole → industrial → narrow design → customized", suitable for different installation spaces and scene requirements;

Safety compliance: Clarify standard certification and safety features to help users avoid electrical safety risks;

Maintenance convenience: Detailed list of accessory system and maintenance specifications to reduce later operation and maintenance costs.