LTR-GPS Installation and Setup Guide
CHAPTER 1
Welcome
Lathem’s LTR-GPS is a Global Positioning Satellite receiver using 12-channels to
access the accurate date and time signal transmitted each second by 24 satellites in
geosynchronous orbit around the globe.
The package includes an amplified GPS Antenna, which must be mounted out-doors
or beneath a roof sky-light, facing skyward. An integrated cable links the Antenna to
the LTR-GPS Receiver Module, which should be mounted in-doors.
The Receiver Module verifies and reformats the received satellite data, and offers
multiple synchronization protocol outputs:
The RS-485 Output can directly synchronize up to 31 Lathem time products, up to
4000ft away, over a single twisted-pair from a user-provided Cat-3 or Cat-5 cable.
The length of cable and number of synchronized devices can be further increased
using Lathem’s “SWIFT485+” RS-485 Converter / Repeater.
An included RS-232 interface provides a periodic “Time Stamp” transmission,
“MM-DD-YYYY HH:MM:SS cr”, for use by computing systems having custom
software to incorporate accurate date and time records in their applications: 9600,
N, 8, 1. Use of this option requires Lathem cable, Part No. SAE0370, to be
ordered separately.
Simple DIP-Switch set-up enables the installer to specify Local Time Zone, Daylight
Savings Time corrections, and output formats. An LED indicator shows Signal
Reception / Protocol Mode.
The LTR-GPS may receive its power from an LTRx-512-series Master Clock, using
2nd cable pair, if the distance is less than 200ft; else, power is provided locally by a
9vAC Power Adapter.
.
Page 1
