Chapter 4
– Service, Configuration & Testing
27
FT742-DM (4-20mA)
– Sensors
- User Manual
4.4 The Acu Test Evaluation PC Software
To help users carry out a test bench assessment of the sensors, FT Technologies sells an Acu-Test Evaluation
Pack. The Evaluation Pack includes the FT055 cable to connect the sensor to an external power supply. The
cable is also fitted with a USB connector to connect the sensor directly to a PC so that its settings can be
checked and configured. There are also colour coded wires allowing the current loops to be measured with a
multimeter or oscilloscope. (See Figure 15)
The pack also includes the Acu Vis software to allow for reviewing and changing a limited number of sensor
settings.
The Acu-Test software is supplied on a CD and will work on PCs running Windows XP, Vista, 7, 8, 8.1 and 10.
The sensors can be easily tested by connecting a DC ammeter in series with each current loop. A positive
supply must be provided to one of the current loop wires. The other wire must then be connected through an
ammeter to ground. This is because the current loops
sink
current, they do not source it. Figure 15 shows how
the Evaluation Pack can be quickly set up to evaluate the current loops.
Figure 15: Evaluation Pack Current Loop Set Up
Note 1) The current loops are polarity insensitive so the yellow wire connection can be swapped with green and
purple swapped with grey.
Note 2) The USB connection can only be used with the Acu Vis PC software.
Note 3) The DC power supply must be able to supply the full heater current of up to 6A. The heater will
automatically turn-on if the ambient temperature is below the programmed set point (the recommended setting
is 30°C).
