Overflow Monitoring

Introduction

The TSX AEY 1614 module allows the user to select between 1 voltage range and 6 thermocouple ranges for each input.

The module always checks for overflow in the selected range: it ensures that the measurement falls between a lower and an upper threshold.

This monitoring is optional.

Measurement Areas

The measurement range is divided into 3 areas:

Nominal Area

Measurement range matching the chosen range.

Overflow Area

Area located beyond the upper threshold.

Underflow Area

Area located below the lower threshold.

NOTE: Beyond these thresholds (overflow or underflow areas) that correspond to nominal values for the chosen range (threshold values of the thermocouples, or -80mV and +80mV for the electric range), one observes measurement saturation, even if over/underflow control was not selected.

Overflow Flags

In over/underflow areas, there is a risk of saturating the measurement device. In order to counter this risk through the user program, error bits have been prepared:

Bit Name	Meaning (when = 1)
%Ir.m.c.ERR	Channel Fault.
%MWr.m.c.2.1	Denotes a range overflow on the channel.
%MWr.m.c.2.14	Denotes a range underflow on the channel.
%MWr.m.c.2.15	Denotes an underflow on the channel.

NOTE: If the under/overflow monitoring is disabled, all of the above bits remain set to 0, whatever the masurement value.

"In Temperature" Range

The ranger under/overflow corresponds either to a dynamic under/overflow of the acquisition device, or to an under/overflow of the sensor's normalized measurement area, or again to a dynamic under/overflow of the cold junction compensation temperature (from -5°C to +85°C).