DIN Rail Terminals & Accessories

DIN rail terminals (also called terminal blocks or terminal strips) are modular electrical connectors designed to mount on standardized metal rails inside electrical enclosures and control panels. They provide organized, secure connection points for joining wires together or connecting wires to electrical devices. The "DIN" designation refers to the German Institute for Standardization (Deutsches Institut für Normung) that established the dimensional standards. DIN rail terminals snap onto TS35 mounting rails (35mm wide x 7.5mm deep) specified by IEC 60715, creating rows of connection points that simplify wiring, save space, and make circuits easy to test and maintain.

Screw Terminals (Screw-Clamp Connection):

• Wire is secured by tightening a screw against the conductor
• Requires screwdriver for installation and removal
• Very secure and reliable connection
• Best for: solid wires, permanent installations, industrial environments
• Lower cost than spring terminals
• Can loosen over time with vibration (requires maintenance checks)

Spring Terminals (Spring-Cage or Push-In Connection):

• Wire is held by spring pressure - no tools required
• Insert wire by pressing a release lever or button
• Tool-free installation saves significant time
• Best for: stranded wire, maintenance-intensive applications, frequent modifications
• More expensive than screw terminals
• Vibration-proof - spring maintains constant pressure
• Faster installation (up to 50% time saving)

Recommendation: Choose screw terminals for cost-sensitive permanent installations. Choose spring terminals for applications requiring frequent modifications, fast installation, or tool-free maintenance.

Double-deck and triple-deck terminals are space-saving designs that stack multiple connection points vertically within a single terminal width:

Double-Deck Terminals:

• Two independent connection levels stacked vertically
• Takes up the width of one standard terminal but provides two connection points
• Saves 50% panel width compared to two separate terminals
• Ideal for control circuits, sensor wiring, and signal distribution

Triple-Deck Terminals:

• Three independent connection levels in one terminal width
• Saves 66% panel width compared to three separate terminals
• Maximum space efficiency for ultra-compact panels

Applications: Multi-deck terminals are essential when panel space is limited, such as compact PLCs, distributed I/O systems, or installations where DIN rail mounting space is constrained. Each level is electrically isolated and can carry different circuits, voltages, or signals.

Important: Ensure your enclosure depth can accommodate the additional projection of multi-deck terminals (they extend further from the DIN rail than single-level terminals).

TS35 is the industry-standard DIN mounting rail specified by IEC 60715. The designation means:

• T = Top-hat profile (hat-shaped cross-section)
• S = Symmetrical design
• 35 = 35mm width

Dimensions:

• Width: 35mm
• Depth: 7.5mm (standard) or 15mm (deep profile)
• Material: Galvanized steel or aluminum
• Available in: Slotted (with mounting holes) or unslotted versions

Why TS35 is Universal: TS35 is the global standard for industrial automation and control equipment. Terminal blocks, circuit breakers, PLCs, power supplies, relays, and other DIN rail mountable devices from any manufacturer will fit TS35 rail. This standardization allows mixing equipment from different manufacturers in the same panel and ensures future expandability.

Other Standards: TS15 (15mm wide) and TS32 (32mm wide) exist but are less common. TS35 is used in 95%+ of industrial control panels worldwide.

DIN rail end stops (also called end brackets or end clamps) are small plastic or metal clips that secure terminal blocks at the ends of a DIN rail row, preventing terminals from sliding along the rail during installation, vibration, or maintenance.

Why They're Essential:

• Prevent sliding: Terminals can easily slide along the rail if not secured
• Maintain spacing: Keep terminals in intended positions during wiring
• Vibration resistance: Stop terminals from migrating in high-vibration environments
• Professional finish: Create clean, organized terminal rows
• Safety:

Installation: End stops simply snap onto the DIN rail at each end of a terminal row. For mid-rail organization, use them between different circuit groups to create clear separation.

Types Available

• Standard end stops (6mm, 10mm widths matching terminal sizes)
• Screwless snap-on (tool-free)
• Screw-fixed (extra security for mobile equipment)
• Marking card holders (combined end stop and labeling)

End stops cost pennies but prevent costly maintenance issues and demonstrate professional installation standards.

Technically yes, but with important considerations:

What's Universal:

• TS35 DIN rail mounting is standardized - terminals from any manufacturer fit the same rail
• Basic mounting and electrical function will work

What's NOT Universal

• Width dimensions vary between manufacturers (even for same wire size)
• Accessory compatibility - end stops, jumper bars, marking systems are brand-specific
• Colour coding may differ between manufacturers
• Test point positions and sizes vary
• Connection methods (screw types, spring mechanisms) differ

Best Practices:

• Use same brand within a terminal row for consistent appearance and accessory compatibility
• Different rows can be different brands if needed
• Document your standard - stick with one or two preferred brands
• Check jumper compatibility - cross-brand jumper bridges often don't fit
• Keep spare accessories for each brand you stock

Mixing brands is acceptable when matching existing installations or when specific technical requirements demand a particular manufacturer's product.

Partition plates (also called separation plates or divider plates) are thin insulating barriers inserted between terminal blocks to create physical and electrical separation between different circuits or voltage levels.

Primary Functions:

1. Safety Separation:

• Physically separate different voltage levels (e.g., 24V DC control from 400V AC power)
• Prevent accidental contact between adjacent circuits
• Meet electrical code requirements for voltage separation

2. Circuit Organisation:

• Visually separate functional groups (inputs, outputs, power, signals)
• Create clear boundaries between equipment zones
• Improve troubleshooting by grouping related circuits

3. Enhanced Creepage/Clearance:

• Increase electrical spacing between high-voltage circuits
• Meet IEC 60664 spacing requirements for different pollution degrees
• Enable closer mounting of incompatible voltage levels

When to Use Partition Plates:

• Between control circuits (24V) and power circuits (230V/400V)
• Separating different equipment zones in large panels
• Between analog signals and switching power supplies (noise isolation)
• Wherever electrical codes require physical separation
• To clearly mark beginning/end of functional circuit groups

Installation: Partition plates simply snap onto the DIN rail between terminals. They typically come in standard widths (6mm, 10mm) and provide a visible orange, yellow, or grey divider.