7
Internal diagnostics
4 Safety
Instruction book, IQAN
4
Safety
Internal diagnostics
The module performs a number of self-checks that improve safety. Checks include
monitoring of voltage supplies, checksums on memory and a watchdog that monitors
software execution. The module is using a real time operating system which supervises
software execution.
If a critical error is detected, the module is stopped, with CAN-bus and outputs off.
CAN-bus interruption
The IQAN modules communicate on a CAN-bus. Both the master module and
expansion modules check for any interruptions in CAN-bus communication. If an error
occurs the master will use zero or an application defined error value for the module
inputs, and the module outputs will be off.
The error will be presented on the master/display module, if there is one, and with a
related blink code on the IQAN module status LEDs.
Current check
For modules with proportional outputs, when used in current mode a current check is
performed. If an error is detected, this will be indicated on the master module, and the
output will shut off.
The module can detect open-circuit, short-circuit to +BAT/-BAT or short-circuit to
other proportional output and return pins.
Emergency stop
W
ARNING
Risk of injury!
The emergency stop must disconnect the power supply to the module; do not connect
the emergency stop as a signal input only.
The emergency stop must be installed so that the risk of reverse feed of the module is
avoided, see section "Supply voltage".
