VIN and VIN32 status

The VIN (0-5 V) and VIN32 (0 -32V) input channels can have the following status values:

• Disabled
• OK
• Low alarm
• High alarm
• Low error
• High error
• Division by zero
• Out of range
• Checksum error
• VREF error
• Error
• No contact (expansion modules)

In the IQANdesign user manual, the section "Value and status" lists all statuses along with information on whether the status generates a dialog message and/or system log event. The status is also seen when measuring in IQANdesign/IQANrun.

Disabled

The status when the function group or the expansion module the VIN is located on is disabled. It is a good design practice to disable optional functions to avoid triggering e.g. low error when an option is not fitted.

OK

The normal status.

Low alarm, High alarm

Value is lower than the specified low alarm level, or higher than specified high alarm level.

The designer can set an alarm level to inform the machine user of a value below or above normal. An example could be high hydraulic oil temperature.

Low error

Voltage is below its valid range. This error can indicate a wiring problem, common problems include open circuit on the signal wire from the sensor, or sensor supply disconnected.

The error detection threshold is automatically calculated from the Min calibration point, as Min/2.

For a sensor with Min set to 500 mV, this means low error is detected < 250mV.

Also see section on Error detection for VIN/VIN32 in IQANdesign user manual.

High error

Voltage is above its valid range. This error can indicate wiring problems such as sensor signal short to 5V. In some cases an open circuit on the sensor ground can give this symptom.

The error detection limit is automatically calculated as

((VINmax- Max)/2)+ Max

For a VIN with Max set to 4500 mV, this means high error is detected > 4750 mV

Division by zero

Min equals max. This error can be avoided by setting limits on the VIN adjust item.

Out of range

Settings are not within limits. Can occur if a machine is updated with an application version with tighter limits on the adjust item.

Checksum error

This would be the status in the unlikely event that settings are corrupted. The fallback is the application defaults for Min and Max are used.

VREF error

There is an error detected on the VREF this channel is connected to.

Error, Critical Error

Critical error is intended for faults detected by module internal diagnostics. In rare cases an undervoltage situation on MC4x can trigger this status on the VIN, before the controller shuts down.

No contact

All I/O on expansion modules are set to the status No contact if the master detects a module timeout.

Error value

When the Voltage input channel status is of status type error (e.g. low error, VREF error), the application will fall back to using the Error value as channel value. The property Error value should be set so that the application is safe also in the event of an error. 

Restart conditions

The input status automatically recover if the error is removed, this should be considered when designing the application. When building restart conditions, the StatusOf() and  StatusTypeOf() functions are useful. For functions with redundant input, the compare channels provide a good way of creating restart conditions.