Parker IQAN-MC31 Instruction Book

9Internal diagnostics4 SafetyInstruction book, IQAN4 SafetyInternal diagnosticsThe module performs a number of self-checks that improve safety. Checks includemonitoring of voltage supplies, checksums on memory and a watchdog that monitorssoftware execution. The module is using a real time operating system which supervisessoftware execution.If a critical error is detected, the module is stopped, with CAN-bus and outputs off.CAN-bus interruptionThe IQAN modules communicate on a CAN-bus. Both the master module andexpansion modules check for any interruptions in CAN-bus communication. If an erroroccurs the master will use zero or an application defined error value for the moduleinputs, and the module outputs will be off.The error will be presented on the master/display module, if there is one, and with arelated blink code on the IQAN module status LEDs.Current checkFor modules with proportional outputs, when used in current mode a current check isperformed. If an error is detected, this will be indicated on the master module, and theoutput will shut off.The module can detect open-circuit, short-circuit to +BAT/-BAT or short-circuit toother proportional output and return pins.Emergency stopW ARNINGRisk of injury!The emergency stop must disconnect the power supply to the module; do not connectthe emergency stop as a signal input only.The emergency stop must be installed so that the risk of reverse feed of the module isavoided, see section "Supply voltage".