Sensitron PL4+

Gas Detection Control Panels - What They Do and When You Need One

A gas detection control panel is the central management unit of a fixed gas detection system. It receives signals from individual gas detectors across an installation, processes alarm levels, and triggers outputs - relay-based alarms, visual and audible warnings, ventilation activation, or shut-off signals - based on pre-configured thresholds. Detectors that output a standard 4–20 mA signal, such as the Sensitron SMART 3G and SMART 3 series, feed directly into the control panel's inputs.

For small installations - a single refrigeration plant room, a compact industrial facility, a small vessel machinery space, or a building with a limited number of monitored zones - the PL4+ provides a purpose-sized control solution. Its 4 on-board inputs cover the most common small-system configurations, with expansion to 8 inputs available via the 4-input expansion module. Output flexibility is substantial for its size: up to 21 programmable outputs via remote modules plus 5 on-board relays, supporting integration with building management systems, alarm panels, and site control infrastructure.

EN 60079-29-1 - The Standard Behind Gas Detection Control Panel Certification

EN 60079-29-1 is the European standard governing the performance requirements for apparatus used to detect and measure flammable gases. ATEX certification to this standard means the PL4+ has been assessed against defined criteria for response time, alarm accuracy, fault detection, and system integrity - not just the general electrical safety requirements that apply to all equipment in hazardous areas.

For operators specifying gas detection systems for classified hazardous areas, a control panel certified to EN 60079-29-1 provides documented evidence of system-level performance that supports class society inspections, regulatory audits, and insurance requirements. When combined with ATEX or IECEx certified detectors from the Sensitron SMART 3G or SMART S series, the PL4+ forms a fully certified system from sensor to control.

Contact us for system configuration advice

Have a question about the Sensitron PL4+?

Our technical team can advise on system configuration, input and output requirements, expansion module selection, and compatibility with Sensitron detector models across the SMART 3G, SMART S, and SMART 3 series.