SERVICE: Fine tune the real time clock in a Power Master Logger

Article ID: 130124sab
Last Reviewed: January 24, 2013

The information in this article applies to:

  • Ranger Power Master Series Data Loggers.

Target Audience.

This article is aimed at:

  • Qualified Service Personnel and Advanced users of the Ranger Product Line.

Summary.

The real time clock chip used in the Power Master series of Loggers has built in frequency correction.
There is a serial command available using TermView that provides access to this fine adjustment.
The notes below detail how to use the serial command.
These instructions are for the PM7000, other Power Master Loggers such as the PM3000, PM2000 and PM1000 may differ very slightly.

Precautions.

BEFORE CHANGING THE SETTING IN THE LOGGER PLEASE BE CERTAIN THAT THE CLOCK AGAINST WHICH THE LOGGER IS BEING CHECKED IS ACCURATE.
It is not recommended that fine adjustment be applied while the recording is in progress, there is a small risk of data corruption.

Before you start.

First follow the instructions for TermView in the knowledgebase here:
APPNOTE: Get started using TermView.exe, the Ranger text terminal utility
on Connecting to a Serial Port
and Selecting the Baud Rate
and Putting the Logger into Text mode

To fine adjust the real time clock in the PM7000.

Enter the command as follows:
PM7000> setclktrim ??
to which the logger will reply with its current trim figure for example:
adjustment = 18
Then to change the clock trim enter (for example)
PM7000> setclktrim 12
to which the logger will reply (in this example)
Clock trim changed from 18 to 12

Notes:
The trim figure can be in the range -31 to +32
The Logger will run faster as a larger positive number is used.
Compared to a trim figure of zero,
a trim of +10 will typically make the Logger GAIN 1 second a day
a trim of -10 will typically make the Logger LOSE 1 second a day

References

APPNOTE: Utilities Installed with Pronto for Windows