Clever circuit design that requires minimal space in the control cabinet
If control cabinet space is limited but machine or system functionality has increased, planners and developers can use a multi-level terminal block like the PT four-level terminal block to address this issue.
Multi-level terminal blocks streamline the structure
The idea of multi-level terminal blocks isn’t new. Like high-rise buildings, the terminal blocks grow in height, not in width. Classic wiring with single-level terminal blocks is like a bungalow with a large footprint. Multi-level terminal blocks save horizontal space on the DIN rail, making it more efficient. Experienced planners may already use double or three-level terminal blocks, but the new PT 2,5-4L four-level terminal block combines all wiring tasks while saving even more space.
The PT 2,5-4L family is an all-rounder
Versatility was key in developing the terminal block family, ideal for space-limited applications. The new four-level terminal block family includes various versions with the same geometry. The classic PT 2,5-4L has four individual levels, allowing connection of different signal types (DI, DO, AI, AO) to a single block.
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Distribution across multiple blocks is also possible. Depending on the controller and space, using one block may be better. It can also support AC and three-phase power distribution, saving space compared to single or double-level blocks. PV versions connect all four levels with a vertical bridge, while standard versions use the FBS-PV potential bridge to connect sublevels. The new FBSW N wire bridges will soon allow connection of distant potentials.
Protection and disconnection
The PT 2,5-4L series features versions with a disconnect base zone (TG) or knife disconnection (MT). The TG version can act as a fuse terminal block with the P-FU 5×20-5 fuse plug, protecting circuits up to 10 A. Lower levels can be used for PE, supply, or signal contacts.
The TG zone offers disconnection and measurement options, ideal for analog control circuits (4…20 mA or 0…10 V). The MT version’s integrated disconnect knife or plug-in isolating plug (P-DI) simplifies commissioning and maintenance. P-CO component connectors allow integration of passive components like diodes or resistors, easily replaceable without special tools.
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Sensor and actuator wiring up to 2.5 mm²
The PT 2,5-4L series is ideal for sensor and actuator wiring. While the PTIO 1,5/S series is limited by its 3.5 mm pitch, the PT 2,5-4L supports 2.5 mm² conductors and 18 A nominal current.
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The PT 2,5-L RD/L BU/L/L modular system can handle power supply on lower levels and signal/actuator applications on upper levels. Versions with integrated LEDs simplify troubleshooting. For shield connections, the PT 2,5-PE/L RD/L BU/L LED 24 RD and PT 2,5-PE/L RD/L BU/L have integrated PE contacts. Alternatively, SCC series shield clamps can connect shielded cables to the busbar.