JUMO railTEMP 902195 Wheelset Temperature Probe for Rail Vehicles (DIN EN 50155)

A railway-qualified probe for axle boxes and hot box detection

The JUMO railTEMP (type 902195) is a wheelset temperature probe for use in rail vehicles according to DIN EN 50155. It is intended for continuous temperature monitoring and hot box detection at difficult-to-access or remote measuring points. The robust sensor has an optional cable protection for harsh environments, offers a choice of high-quality connectors, and can be made in customer-specific versions.

The probe works on the principle of an RTD temperature probe in two-, three- or four-wire circuit. A qualified measuring insert, developed for this application, holds up to two sensing elements: Pt100, Pt1000 or an NTC of 5 kohm. The insert sits in a straight or angled brass process connection and the firmly attached halogen-free connection line can end in bare wires, ferrules or Harting or Gimota connectors. Protection is IP68 and IP69, and the railway certificate CH 23-04-26-004 is issued by RST Rail System Testing and JUMO.

Technical specifications

Configuring a railTEMP probe

The order code reads 902195 / basic extension – version – operating temperature – measuring insert – tolerance class – tube diameter – insertion length – line end – line length – cable protection – protection length / extra codes. Basic extension 10 is the angled screwed flange and 20 the straight screwed flange; version 0 is the standard. Operating temperature 370 is -50 to +150 degC (for NTC inserts) and 380 is -50 to +200 degC (standard). Tube diameter is 5 mm and the insertion length is specified in plain text.

Cable protection code 00 is none, 10 is a plastic corrugated hose and 20 a rubber fabric (hydraulic) hose. Extra codes: 317 shielded line not connected to the process connection, 093 shielding connected to the process connection, 094 shielding fed out on the connection side with a grounding wire, and 519 fastening screws.

Installation and use on rolling stock

The probe must be fitted in a drilled hole or thermowell in the bearing housing, with the hole spacing of the screwed flange matched to the axle-box cover (other hole spacing on request). The brass flange is bolted on, so fastening screws can be added with extra code 519. Route the connection line in its protective hose clear of moving parts, and note that the hose has its own temperature limit of +95 degC for corrugated plastic and +100 degC for rubber fabric, lower than the cable itself.

Shielding should be connected according to the vehicle earthing concept, either at the process connection or through a grounding wire at the connector end. A hot box detector compares the wheelset temperature with limits in the vehicle controller, so a Pt100 or Pt1000 element gives a standard signal for rolling-stock diagnostics. The same type of probe could be used for metros, tramways, locomotives and rail maintenance depots, and the certificate scope should be checked against the project specification.

As general guidance, record the order code printed on the nameplate before requesting a quotation, and keep the data sheet revision with the project documents so that later replacements match the installed device. Tell us the quantity, the delivery location in Oman and any wiring or mounting accessories you also need, and we will confirm availability and lead time for the exact variant.

Documents and quotation

The JUMO data sheet 902195 is attached for download. Seven Star LLC supplies JUMO sensors from Muscat; send the flange type, element, insertion length, cable and connector details and we will quote. More probes appear under https://omansevenstar.com/product-category/sensors-transmitters/temperature/.