What the wide temperature range means in a panel
The Siemens 6AG1055-1HB00-7BA2 is a LOGO! 8 expansion module that adds 4 digital inputs and 4 relay outputs to a LOGO! 8 base unit. At cold restart, the minimum temperature is -25 °C with condensation and frost permitted, though commissioning under condensation conditions is not allowed. This means the module can survive a deep freeze and power up once the enclosure warms above -25 °C.
The narrow footprint leaves room for additional I/O or a power supply in a crowded enclosure. IP20 rated, so it is intended for dry indoor panels only. The conformal coating (Class A) and resistance to coolants, lubricants, diesel, and oil droplets in air make it suitable for machine-tool or engine-test environments where airborne contaminants are present.
Input and output ratings for the BOM
The 4 digital inputs accept AC or DC voltage: signal "1" threshold is >12 V AC/DC, signal "0" is <5 V AC/DC, with a typical input current of 5.5 mA at signal "1". This means the module works with standard 24 V AC/DC sensors and switches without additional interface relays. The 4 relay outputs are rated 5 A resistive and 3 A inductive per channel, with a maximum lamp load of 1000 W. Each output can directly drive a small contactor coil or a solenoid valve up to 3 A inductive, saving an interposing relay. The outputs switch from "0" to "1" in 1.5 ms max and from "1" to "0" in 15 ms max. For fast-cycling loads like a pneumatic valve manifold, the 15 ms off-delay may require a freewheeling diode on the load.
The module is compatible with LOGO! 8 base units (6ED1055-1xx00-0BA2 series and 6ED1055-1xx00-7BA2 series). It is the SIPLUS variant of the standard 6ED1055-1HB00-0BA2, offering extended temperature range and conformal coating for harsh environments.