Ttl Connection; Figure 3: Connecting Ttl And External Power To Addressable Bus - Geokon 8020-38 Instruction Manual

2.1.2 TTL CONNECTION

To connect the Converter to a TTL-capable device, do the following:
1. Connect the RX wire of the logger/reader to the connection labeled RX
[OUT] on the TTL spring terminal.
2. Connect the TX wire of the logger/reader to the connection labeled TX [IN]
on the TTL spring terminal.
3. Connect the external 12 volt supply positive (+) and negative (-) wires to the
connections labeled 12V and GND on the TTL spring terminal, respectively.
4. Connect the shield wire to the connection labeled SHIELD on the TTL spring
terminal as well.
See the figure below.
Note: The TTL signal ground reference MUST be connected to the Addressable
Bus Converter ground, as well as to the ground of the external power supply.
TTL Spring
Terminal
FIGURE 3: Connecting TTL and External Power to Addressable Bus Converter
Secure the ground strap to the earth ground lug using the brass screw included
with the assembly. Attach the other end of the strap to a reliable earth ground
point outside of the enclosure.
MODEL 8020-38 ADDRESSABLE BUS CONVERTER | INSTALLATION | 3
Earth Ground Lug
RS-485 Spring
Terminal