Introduction | Tank Gauge Transmitter |
|
|
1.3Operation
The ATT uses an incremental counting technique for determining liquid level. An initial level is identified as part of the calibration procedure. Changes to that level are determined through incremental increases or decreases detected by the ATT.
The host computer collects measurement information by polling the Advanced Technology Transmitter over a variety of communication interfaces such as EIA485 and Mark/Space. Several communication protocols are supported. Among them are Modbus and Mark/Space.
1.4Configuration
The Varec Model 1200 Handheld Terminal is used to configure the ATT. It connects to the same ATTI bus used to interconnect other input/output devices to the ATT. There is a special connection located inside the junction box for the Handheld Terminal.
1.5Construction
The Advanced Technology Transmitter is housed within an aluminum enclosure. The enclosure and assembly meet explosion proof requirements and are environmentally sealed to prevent internal exposure to contamination.
7.5"
(190 mm)
8 " |
(203 mm) |
6.8 " |
(172 mm) |
12 "
(308 mm)
4"
(101 mm)
3.7"
(94 mm)
3.4"
(86 mm)
Figure 1-2: Model 4000 Advanced Technology Transmitter Assembly
2 | Installation and Operations Manual |