Protronic RZ-24 from 2026: Hold-Open System Control Unit Now in a New, Larger Housing

At the beginning of 2026, Protronic Innovative Steuerungselektronik GmbH will launch an enhanced version of its proven RZ-24 hold-open system control unit. The core component of many hold-open systems will in future be presented in a new, larger housing – offering significantly more space, greater flexibility during installation and optimized application possibilities, even under demanding environmental conditions.

For specialist contractors, planners and operators of hold-open systems, this means: greater installation convenience, more expansion options and, as always, the proven Protronic quality.

New housing – more space, more flexibility

The most noticeable innovation of the RZ-24 from 2026 onwards is the enlarged housing in RAL 7035. It was specifically developed to make installation and wiring significantly easier.

New housing dimensions of the RZ-24 (from 2026)

• Base: 166 × 166 mm

• Overall dimensions (with cover): 175 × 175 × 65 mm

The compact yet enlarged design ensures an optimal balance between available space and minimal wall projection.

The advantages at a glance:

• Flexible cable entry
  Cables can be routed from the top, bottom or rear – ideal for different structural situations.

• More space for clean wiring
  The larger housing provides significantly more room for clear and fast installation.

• Upgradeable & expandable

  • Powerpack 3 (PP3) can be integrated directly into the housing at any time

  • Time relay can be retrofitted optionally

Optimal protection – also suitable for damp environments

Another advantage is the variable degree of protection, depending on the type of cable entry:

• IP65 when using cable glands (top or bottom)
  → ideal for damp rooms and demanding environments

• IP30 with rear cable entry

This makes the RZ-24 suitable for both classic indoor areas and locations with increased requirements.

Proven functions remain unchanged

Despite the innovations, the RZ-24 remains technically what has distinguished it for years: a neutral, reliable hold-open system control unit with extensive features.

Still integrated:

• 3-in-1 system
  Power supply + release device + manual release button incl. reset adapter

• Integrated manual push button

• Reset button and integrated buzzer

• Button “Close door” usable as test button

• Automatic reset after power failure

• Potential-free alarm signaling contact

• Front foil control panel with operating status display

• Power supply: 24 V / max. 0.9 A

• Type approval: Z-6.500-2436

• Approval: Z-6.510-2428

This means that the RZ-24 continues to meet all relevant requirements for the safe operation of hold-open systems.