4. 6 mm ² Series: Electric Drive and Testing
Mainly used for controlling and testing circuits of small and medium power motors.
Test disconnect terminal (STME 6): This is the star product of this series. Specially designed for the secondary circuit of current transformers, only two STME 6 terminals are needed to form a complete testing circuit. Combined with the PAI-4-FIX test adapter and SB-ME switch jumper, safe and convenient open circuit and short circuit operations of the current transformer can be achieved.
Diode terminal: such as STME 6-DIO, used for logic control or reverse voltage protection. The manual clearly states that when the diode load reaches 5A, the surface temperature can reach 140 ° C, and attention should be paid to heat dissipation and protection.
Sliding terminal (SGSK 6): The circuit can be turned on and off by sliding the slider, and multiple measuring devices or protective relays can be connected separately.
5. Series of 10 mm ² and above: Main power distribution
10 mm ² series: including straight through, multi-layer, and hybrid terminals. For example, STU 10/4X2.5, which combines a 10mm ² screw main inlet and four 2.5mm ² spring branch outlets, is very suitable as an on-site distribution box.
16 mm ² series: mainly for straight through and multi wire terminals, capable of carrying currents of up to 90A or more.
35 mm ² series: As the high current solution in the series, the straight through terminal ST 35 can carry 125A current. In addition, there is a neutral wire disconnect terminal STN 35, which is used to disconnect the neutral wire circuit without cutting off other phase lines.

Deep functional analysis: not just connectivity
The design philosophy of the ST series goes far beyond simple wire connections, it is more like a modular electrical functional platform.
1. Flexible bridging and potential allocation
Phoenix has designed a comprehensive bridging attachment system for the ST series, greatly simplifying potential distribution.
Fixed Bridge Components (FBS/FBSR): Can bridge 2 to 50 terminals at once, quickly establishing a common potential point. For example, FBS 2-3.5 is used for 1.5mm ² terminals, and FBS 2-8 is used for 6mm ² and above terminals.
Jumping bridge: By removing specific contact guides on standard bridges, a jumping bridge can be created to achieve parallel transmission of two different potentials.
Reducing bridge: allows the connection of terminals with different cross-sections, such as connecting a 10mm ² power terminal with a 2.5mm ² control terminal to form a power distribution block.
2. Testing and measurement capabilities
The ST series fully considers the testing requirements during the debugging and maintenance phases.
Universal plug-in area: On the disconnect type terminal, a universal plug-in area is provided, which can be compatible with P-FIX isolated feedthrough connectors, P-DI isolated plugs, P-CO component connectors, and P-FU fuse plugs, achieving modular combination of functions.
Standard testing interface: Supports testing plugs with a diameter of 2.3mm. At the same time, we provide testing adapters (such as PAI-4) that are compatible with 4mm diameter safety test plugs and support quick connections with all mainstream multimeters and testing instruments.
3. Visual and electrical isolation
Partition plates, such as the D-ST... series, have a contour higher than the terminal body, providing not only electrical isolation but also clear visual grouping to prevent accidental contact between circuits of different voltage levels.
Cover segments: Used to cover the unused protruding parts of three or four layer terminals. When two layers of terminals are installed side by side, it can effectively prevent fingers from touching live parts and meet the highest safety standards.
4. Hybrid Terminal: Integration of Connection Technologies
The STS and STU series hybrid terminals are an ideal choice for meeting the requirements of heterogeneous connections. They integrate two connection methods, spring cage and screw, into one terminal. For example, in the STS 2.5 series, the spring side can quickly connect thin wires from sensors, while the screw side can firmly connect thick cables from power sources. This design is particularly practical when it comes to retrofitting projects and interconnecting different standard devices.
Installation and Attachment System Detailed Explanation
A complete wiring plan cannot do without thoughtful accessories. The ST series accessory system includes:
Marking system: Provides central marking slots (compatible with UC-TM or ZB series marking strips) and side marking slots (compatible with UC-TMF or ZBF series) to ensure that each connection point can be clearly and permanently identified.
DIN rail: compatible with standard NS 35/7.5 and NS 35/15 rails. For the MSB series of miniature terminals, it also supports 15mm wide DIN rails for ultra-thin installation.
End plate/partition: such as D-ST 2.5, used to seal the end of the terminal group and increase the creepage distance.
Operating tool: It is recommended to use SZF series screwdrivers (such as SZF 1-0.6X3.5), whose size precisely matches the spring release hole to avoid damaging the terminals.