RKI Instruments GX6000

Up to six simultaneously. Four channels are fixed for confined-space entry: combustible gas/methane (catalytic, %LEL), oxygen (%vol), carbon monoxide (ppm), and hydrogen sulfide (ppm). Two further smart slots each accept a PID (VOC), an infrared sensor (CO2, methane, or hydrocarbons), or a super-toxic electrochemical sensor (NH3, Cl2, HCN, NO2, PH3, SO2).

It can hold two PID sensors at once (an industry first), for example a broad-range 10.6 eV lamp for general VOCs alongside a benzene-specific 10.0 eV lamp, so you get general VOC detection and targeted benzene analysis without swapping sensors. An 11.7 eV lamp is also available, and the VOC library holds over 600 compounds.

As two generic analog channels (Ch1 and Ch2). Each smart slot auto-recognizes whichever sensor is fitted, but the value is a plain reading that depends on that sensor, so the integration ingests it generically rather than as a fixed gas. The four confined-space gases (combustible/CH4, O2, CO, H2S) are always reported by name.

Yes. The GM460 was TSI's rebadged version of the GX-6000 (the same six-channel platform and sensor options), now discontinued by TSI. The Thiamis driver reads both and auto-detects which one is connected.

Over an RS-232 serial link (921600 baud, 8 data bits, odd parity); the driver polls the instrument each interval and parses the reply. The sample-draw pump runs at 0.45 LPM. Battery voltage is carried in the protocol but is not surfaced as a measured parameter.