Hach SP-510 Basis-Benutzerhandbuch Seite 21

Problem
The SOFT LED light is on but the
pump motor does not operate.
The reading is continually high. The
HARD LED is on.
The HARD LED is flashing.
The SOFT LED is flashing
continuously for more than 5 minutes
after the power is set to on.
Troubleshooting for a hard reading
When the red LED is on continuously and the instrument measures hard water, do the steps that
follow.
Cause
If the flow is too low, the
sample cell does not flush
completely all the color out of
the colorimeter. This causes a
zero reading. If the flow is too
high, some of the water will
bypass the pinch block and
cause the color to be diluted.
The sample line is pinched off
in the pinch block.
Possible cause
Operation power is low
Voltage selector setting is
not correct
Motor cable is not connected
Motor does not operate
• No stir bar
• LED is not connected
• No sample flow
• Out of reagents
The instrument could not
save the calibration
information.
The instrument could not
save the disabled alarm
status.
The optical path has a
blockage or the optical
switch does not work.
Solution
Make sure to set the flow rate to 200 mL/minute.
• Pull the sample line from the colorimeter. Water that is already in the line
could leak out. Examine and adjust the flow rate when a steady water
stream comes out while the line is pinched. Set the flow rate to
200 mL/minute.
• Make sure that the pressure plate of the pinch block is not overtightened.
• Examine the back of the pinch blocks and make sure that they do not have
grooves.
Solution
Make sure that the line voltage is within
specification.
Set the line voltage selector switch to the
correct voltage.
Connect the motor cable connection.
Replace the motor.
Refer to Troubleshooting for a hard
reading on page 21. If the problem
continues, cycle power to the instrument,
examine all power connections and fuses,
replace the circuit board or contact
technical support.
Contact technical support.
• Let the instrument complete the cycle.
• Make sure that the motor operates.
• Set the power to off and then to on and
wait for 5 minutes.
• Contact technical support.
English 21