Panel fit and I/O assignment
The Siemens 6ED1055-1HB00-0BA0 is a LOGO! DM8 24R expansion module that snaps onto a 35 mm DIN rail, occupying 2 spacing units (36 mm wide). It adds 4 digital inputs and 4 relay outputs to a LOGO! base unit — the relay contacts handle up to 5 A on resistive loads and 3 A on inductive loads, so it directly drives small contactors, solenoid valves, or indicator banks without an interposing relay. The input side accepts 24 V AC or DC (range 20.4–28.8 V DC, 47–63 Hz AC) and thresholds are set for industrial 24 V signals: a logic '1' requires at least 12 V with a typical draw of 2.5 mA, while a logic '0' is guaranteed below 5 V. This means it works with standard 24 V PLC sensors and pushbuttons, and the AC capability lets it also read 24 V AC control transformer outputs directly.
Output ratings and switching limits
Each relay output is rated 5 A continuous on resistive loads and 3 A on inductive loads. For lamp loads the maximum is 1,000 W. Mechanical switching frequency is 10 Hz max, which is typical for relay outputs — adequate for valve or contactor cycling, but not for high-speed pulse trains. The input transition from '0' to '1' takes 1.5 ms max, and from '1' to '0' takes 15 ms max, so fast encoder pulses or short-duration sensor signals may be missed without external signal conditioning.
Approvals include UL, CSA, FM, and marine certification, plus CE and VDE 0631 compliance. It carries an FM approval for use in residential areas (limit class B), which simplifies panel approvals for light-commercial installations.