1756-OF8IH Allen-Bradley | ControlLogix 8 Pt A/O HART Isolated

The 1756-OF8IH ControlLogix HART Output Module by Allen-Bradley is an output module with 8 isolated differential current outputs and 1 HART modem per channel and it is installed in any 1756 I/O chassis slot. The 1756-OF8IH has an output range of 0-20mA and 4-20mA with 15 bits channel resolution across 24mA and it draws an estimated 400mA backplane current at 24V DC. It provides Open Circuit Detection with over-voltage protection at ±24V DC and it offers output short-circuit protection by electronically limiting the output current to a value not greater than 21mA (<=21mA). The module has 50-750 (with short circuit survival) Drive Capability with a load reactance of 10H and it has a load-dependent settling time less than 100ms with HART-enabled and less than 23ms with HART disabled. 

The 1756-OF8IH has calibration accuracy of 0.15% at 4-20mA and requires calibration at a standard time interval of 12 months. It has ±3 ppm full-scale OFFSET drift with a GAIN drift of ±4 ppm and a module error of 0.3% at 4-20mA. The 1756-OF8IH has an estimated module HART scan time of 1s with IEEE 32-bit floating point data format and it uses the R-Ladder DAC output conversion method. It provides 250V voltage isolation between outputs-to-backplane using reinforced insulation tested at 3535V DC for 60s and 250V voltage isolation between output-to-output and output- to-ground using basic insulation tested for 60s at 2120V DC. Its circuit uses copper wire and the whole module is designated T4A (North America) and T4ATEX and EIC temperature codes. The 1756-OF8IH has a 0-60 °C working temperature range at 5-95% non-condensing humidity and an ambient temperature of 60 °C (140 °F).