What this module is
The 6AG1055-1HB00-2BY0: It runs from -40 °C to 70 °C, covering unconditioned cabinets where the ambient drops well below zero.
Ratings that drive the fit decision
Relay contacts are rated 5 A resistive per point, but the inductive ceiling is 3 A per relay, and the resistive figure halves to 3 A above 55 °C with a 5 A / 10 A-burst allow-and-decay shape — meaning the continuous current a wireman can assume is 3 A per point in a hot cabinet, not 5 A. Outputs carry no built-in short-circuit protection, so the branch protection has to live upstream in the panel — that decides the fusing layout on every drawing. Supply window is 20.4–28.8 V DC, but it tightens to 22–27.5 V once the cabinet runs above 55 °C; if a retrofit lands in a hot enclosure, the DC rail tolerance shrinks and a buck-rated PSU may stop being acceptable. Operating temperature spans -40 °C to 70 °C, with the UL/cUL use file accepting up to 55 °C — the wider -40 to 70 range is the industrial envelope, but the UL recognition is what governs a North American panel. Installation altitude is rated to 5 000 m with a stepped derate — Tmax − 10 K above 2 000 m and Tmax − 20 K above 3 500 m — so a high-elevation site loses thermal headroom, not the part's ability to be installed.
Where it lands in a panel
With four relay outputs and four digital inputs, the module is sized for distributed control of small loads — pilot relays, solenoid valves, contactor coils, small heater bands, signal lamps — typically as a remote or stand-alone I/O island beside a master LOGO! or third-party controller.
Approvals — what is and is not on the file
FM approval, CSA approval and marine approval are not on the file — hazardous-area deployments, Canadian-only panels where CSA marking is called up, and shipboard installations are out of scope on this order code.
Sourcing posture
Production status is recorded as Active in the lifecycle record, so the code remains on the official channel — for a current BOM line it is specified into the BOM and quoted to order against an RFQ, with no need to chase last-time-buy windows today.
Close-out for the BOM line
For a panel that needs 4 relay outputs at 5 A resistive with a -40 °C cold-start envelope and UL listing, this code is the fit; for a Canadian-marked or marine application it is not — a request for quotation on the order code confirms current availability, the unit-of-origin trace and the UL file carry-over.