YSI 6500 Environmental Process Monitor - Manual (Page 56)

SECTION 6 TROUBLESHOOTING
The following section is designed to identify and correct the most common problems that you
might encounter when using your 6500/6-Series system in a stream. Included are symptoms that
involve:
♦ Communication between the 6500 Monitor and the 6-Series Sonde
♦ Enabling/disabling menu choices on the 6500 display screen
♦ Calibration Error Messages
♦ Sensor accuracy and repeatability problems related to either physical deployment or sensor
malfunction
♦ Alarm functionality
♦ 4-20 mA current loop functionality
For additional troubleshooting information with regard to the sonde and its sensors, consult Section 7
of the manual supplied with your 6-Series Sonde.
6.1 COMMUNICATION PROBLEMS
Symptom: The 6500 shows no display (with or without the sonde
connected).
Possible Cause and Suggested Action: The contrast of your display might have been altered
and/or is inappropriate for the present lighting conditions. Press and hold the Cal key while
using the up and down arrow keys to alter the contrast. If this does not result in the appearance of
a display, AC power may not be supplied to the 6500 from the main’s line. First, make sure that
the AC circuit is active. Check switch boxes and breakers. If not active, activate it.
If power is being supplied but no display is present, the power lead connection to the box may be
loose.
WARNING!
Turn off the power to the 6500 before proceeding with the check.
We recommend that the following tests should be carried out only by a qualified electrician or
electronic engineer due to the danger of electric shock.
Loosen the 4 screws that attach the front cover to the 6500 Monitor enclosure. Swing the front cover
to the left, leaving the ribbon cable attached. Examine the power connection on the top right of the
box and make sure that the AC input wires are securely attached to the connector and that the
connector is firmly plugged into the board. After proper connections have been assured, replace the