Teledyne 440, System Manual, Page: 61 / 256

4 – Electrical Installation
DPN 402196 Issue 4.1 © Teledyne TSS 4- 15
4.2.3 Interface to Data Logger
Use the SDC port ‘COM3 (EXT O/P) ’
During normal survey operations, the 440 System acquires data at a rate of up to 1MB per hour. You
should arrange to record the official survey log on a suitable data logger.
For your convenience and for test purposes, the 440 System can also create a logged record internally
on the SDC hard disk. Data stored using the internal logging facility does not possess the same format
as that transmitted to the external data logger, and you should not use it as the primary survey log.
Internal logging allows you to record sections of the survey and then to ‘replay’ them subsequently
using the graphical display facilities of the SDC. You cannot replay external logging files through the
SDC in this way.
NOTE
The internal logging facility on the 440 System is for your convenience and for test
purposes only. Do not use it as the principal survey logging tool. Unless otherwise
stated, this Manual describes the external logging facility of the 440 System.
See section 6.4.1.1 "External Logging Format" on page 6-23 for a description of the format that the 440
System uses to log data.
Make a connection between the 440 System and an external data logger using the 9-way D-type
‘COM3 (EXT O/P)’ port on the Panel PC rear comms module. The pin designations for this port are as
follows:
Table 4-9: RS232 connection to SDC ‘COM3 (EXT O/P)
Signal to Data Logger SDC ‘LOG O/P’ (COM3) Pin connections
RS232 input to data logger 3 (transmit)
RS232 common 5 (ground)