5.2 Distribution Box

The STS Distribution Box has an independent 16-bit processor to monitor the battery, control the modem power, perform Built-In-Test (BIT) functions and select the Levelogger communication channels.

The Distribution Box has labeled connections for the STS Controller; a 12V sealed lead-acid battery, the modem and modem power. The two-wire connectors for four dataloggers are also clearly indicated on the Box. There are two other connections reserved for alternative power sources; these options will be discussed in Section 6.1.


solinst sts telemetry systems distribution box sts controller connections regulator connection external power connection battery connection modem connection pc connection computer connection computer interface modem power connection sts fuse image

Figure 5-6 Distribution Box


To remove the Reader Cable connector pins from the Distribution Box, press the white plugs above each connection into the Distribution Box, while pulling the connector pins out.


There is a LED indicator on the bottom left of the Distribution Box. Under normal operation, the LED will flash green every minute. The LED will flash red if a failure is detected. The following are possible errors that may have occurred:


If the LED indicator is not flashing green or red, the 8A SLO-BLO fuse may need to be checked. This could mean no power is going from the battery to the Distribution Box.

  1. The battery voltage is too low (i.e. < 9V).
  2. The Distribution box fuse has blown.
  3. The internal regulator voltage is out of tolerance.
  4. Program Memory test failed.
  5. Electrically Erasable Programmable memory test fail.

It is suggested to do the following if a red LED is shown:

  1. For a System using a 12V battery only, you most likely need to recharge or replace the battery.
  2. Pull the fuse out of the Distribution Box and check it. Replace it, if it is broken. Replacement fuses are available from Solinst.
  3. For a System using a solar panel, check the solar panel and regulator connections. Check the output voltage on the solar panel (It should be 13V or more in order to recharge the battery). If it is greater than 17V, it may be an indication that the battery is disconnected. The battery must be connected.
  4. For a System using an AC Charger, check the output voltage on the charger. It should be approximately 14.5V.

The LED will flash green if the error has been corrected. If none of the above actions correct the error, check all connections in the STS Remote Station. If the LED is still red, contact Solinst for further assistance (errors 3,4, or 5 may have occurred).