Guralp Systems Limited
MAN-ELP-0119 - ELP-0119 and ELP-0120 - Technical Manual

Chapter 3. Deployment

3.1 The ELP-0119 GPS receiver interface

The ELP-0119 should be placed at the GPS receiver end of the TIA/EIA-422 link. It requires an external DC power supply capable of providing 500 mW or above at between 10 and 35 Volts. The output from the power supply is passed unmodified to the GPS receiver. The GPS receiver should be connected using a standard Güralp ten-pin GPS cable, part number CAS-BDA-0029.

The interface to the twisted-pair cable is via a modular 8P8C connector, commonly known (incorrectly) as RJ45.

3.2 The ELP-0120 digitiser interface

The ELP-0120 should be placed at the digitiser end of the TIA/EIA-422 link. The device should be connected to the GPS input of the digitiser using a standard Güralp 10-pin GPS cable, part number CAS-BDA-0029.

The interface to the twisted-pair cable is via a modular 8P8C connector, commonly known (incorrectly) as RJ45.

3.3 The cable

The two devices should be connected by up to 150 metres of twisted-pair cable. Standard Cat5, Cat5e or Cat6 cable is suitable but any cable that:

can be used.

Note: The TIA/EIA422 specification allows for up to one kilometre of cable but, at the time of writing, the system has only been tested using 150 metres of Cat 5e cable.

The cable should be connected “pin for pin”; i.e. pin one at the ELP-0119 should be connected to pin one at the ELP-0120, pin two to pin two, and so on. A twisted pair should be used for the two NMEA signals and another for the two PPS signals, as described in the pin-out pages (section 4.1.3 and section 4.2.2). If the chosen cable has both a ground wire and a screen, the screen should be connected to ground only at the ELP-0119 (GPS receiver) end.