Starting at $450.00
  • Usually ships in 7-10 business days



  • Stand alone system
  • LEL or PPM detection ranges available for many gases
  • Highest practical LEL alarm point is 30% LEL
  • Input voltages:
    • 24 VDC (standard)
    • 115 VAC (optional; includes power cord)
    • 48 VDC (optional)
  • 2 alarm levels
  • Audible and visual alarms
  • Relay contacts rated 12A @ 115 VAC
An engineer will contact you to confirm your application requirements (gas type, concentration, etc.) prior to finalizing your order


The RKI Instruments PS 2 combustible gas monitor is a multi-purpose, stand alone unit with an MOS (metal oxide semiconductor) for long lasting and low maintenance detection at the LEL or PPM levels of many gases or vapors. Since the PS 2 sensor is a general hydrocarbon sensor, it is not specific to any particular gas It has two alarm levels for increasing gas or vapor levels, at the PPM level for detection of many solvent vapors, or for LEL level detection of flammable vapors. Each alarm level activates a 12 amp relay inside the unit, and terminals are provided for wiring the relay to activate an external alarming device or some other device such as a ventilation fan.

This RKI Instruments unit is housed in a durable plastic enclosure with flanges provided for wall mounting and is designed with easy access wiring hubs on the bottom of the unit. The front of the PS 2 contains three lights; Pilot, Alarm 1, and Alarm 2. An internal audible alarm (85 db) is also built in which activates in a gas alarm condition. The standard PS 2 is supplied with the gas sensor located on the end of a 30 foot cable (other cable distances are also available). Each unit is powered by 24 VDC as standard (115 VAC or 48 VDC versions optional) and the AC version comes complete with a 6 foot power cord.

Common applications for the RKI Instruments PS 2 combustible gas monitor include battery storage and charging locations, petrochemical plants, refineries, water and wastewater treatment plants, gas, telephone and electric utilities, manufacturing facilities, steel, automotive, HVAC and buildings on landfill.


Here's how some of our customers use this product...

Battery Room Monitoring

The Background: Our customer maintains a facility that includes a large room used to store and charge lead-acid batteries. They seek a means of monitoring the space for the lower explosive limit for hydrogen gas.

The Problem: Overcharging lead-acid batteries can result in the release of hydrogen gas, creating a potentially explosive atmosphere. The customer needs to monitor LEL at multiple locations in the room and activate a strobe and horn outside of the room when LEL is exceeded.

The Solution: We recommended the RKI Instruments PS 2 combustible gas monitor, a multi-purpose, stand-alone unit with a long lasting, low maintenance sensor for detecting LEL or PPM levels of many gases or vapors. The PS 2 is a cost-effective solution and includes internal relays for alarms and strobes.