Thermo Scientific AquaSensors
™
AquaChlor
™
Free Chlorine Monitor User Guide
19
5.
AV38 Local Display Interface
For detailed information on configuration of AV38 current outputs, relays, host communications, please refer to
the AV38 manual (MAN018AV38). This manual will describe basic calibration, configuration and chlorine/pH
compensation functions directly related to free chlorine measurements
The AV38 is a universal display interface for DataStick sensor systems that includes the free chorine
measurement. The enclosure has ¼ DIN dimensions for easy mounting and is rated NEMA 4X for outdoor use.
It uses a liquid crystal display (LCD) with a high contrast backlight for best readability and is powered with 24
volts DC or optionally with line power (90 VAC to 240 VAC).
The AV38 automatically recognizes the type of DataStick connected to the system and
provides the appropriate calibration, configuration and diagnostic menus. It has options
for two 4-20 current outputs, two alarm/control/wash relays and network
communications to a host computer. In addition, the AV38 can address up to 247
DataStick sensors.
DataStick sensors connected to the AV38 communicate via Modbus RTU. As such,
the AV38 can be used to select any two of the DataStick sensors on the bus for
display, current output reporting and relay alarms by selecting the desired station
addresses. When there is no DataStick sensor connected at the selected network address, the measure screen
will indicate “DataStick Absent”.
There are seven keys for menu navigation. The MENU key is used to toggle between the menu and the
measure screen. Pressing the Menu key provides options for calibration, configuration, communications,
outputs and relays. Refer to the AV38 Manual for Details.
5.1.
Measure Screen Overview
The AV38 user interface is shown in Figure 5.1. It consists of an LCD module that contains two lines of 16
alphanumeric characters and seven keys to navigate the menu. The contrast of the LCD module can be
adjusted by simultaneously pressing the escape and up-arrow keys (for more contrast) or the escape and
down-arrow keys (for less contrast).
When the DataStick and communications adapter are connected to the AV38 display but the sensor head
is absent, the measure screen indicates the fault as shown in Figure 5.2.
1.34 ppm AB
30.8 °C DS1: 6
MENU
ESC
ENTER
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▲
►
▼
Figure 5.1:
The elements of the measure screen
