User's Manual

Introduction to the TTMS System
TTMS Reader
Tanker Truck Monitoring System- User’s Guide 11
1.3.4 Display Unit and Protection Unit
The Display unit is located inside the truck's cabin. It provides the operator a local visual
summary of the condition of the seals (tampered or OK). The TTMS system supports two Seal
Status Indicator boxes: one for each tank – according to the truck configuration. The Seal Status
Indicator interfaces to the TTMS System (specifically to the AVL Reader unit) through a
Protection Box.
Both units are described in the following sections.
1.3.4.1 Seal Status Indicator
The seal status indicator unit provides status indication of the tamper conditions of all hatches
and valve seals. The unit is powered from protection unit (+12VDC regulated). It supports 16
LEDs that corresponding to each hatch or valve sensor of the tanker. Each Seal Status Indicator
unit communicates with the AVL Reader over RS-485 serial communication protocol.
NOTE: For trucks supporting two tanks, two units are installed.
Each Seal Status Indicator unit contains two rows of LED displays, corresponding to the hatches
and valves and a set of system LEDs providing general status information. The LEDs are lit RED
or GREEN according to the status of the seal ( Table
1-6).
Figure 1-5. Display Unit
LEDs corresponding to seals
installed on hatches/valves
General indicators
Bracket
RS485 port with cable