Under/Overshoot Monitoring on Inputs

Introduction

The TBX AMS 620 module provides a choice between voltage and current ranges.

For the selected range, the module performs an overflow check: it checks that the measurement is between a lower and upper limit.

Measurement Areas

The measurement area is located in the nominal area.

Above the nominal area, the overflow is tolerated up to the overflow limits.

Illustration:

Under/Overflow Identifiers

If the values provided by the application are outside the limits, the value of the overshot limit is saturated.

The module continues to provide the converted value until saturation of the converter or the display format (+32767/-32768), even though the validity of the measurement is not guaranteed.

The user can, via the overflow bit, avoid taking these measurements into account.

Overflow bit:

Bit name	Meaning
%I\2.e\0.m.c.ERR	If equal to 1, this indicates a range overflow on the channel.

Overflow Values of the Electrical Ranges

For voltage ranges, the module authorizes a 5% overflow for the positive electrical scope covered by the range.

Overflow values according to input type

Range	Lower limit	Upper limit
+/-10 V	-10.5 V	+10.5 V
0..5 V	0 V: this overflow is not detected	+5.25 V
0..20 mA	0 V: this overflow is not detected	+21 mA
4..20 mA	+3.2 mA	+20.8 mA