Hach SP-51 Manual Básico Del Usuario página 21

Section 10 Troubleshooting
Problem
The SOFT LED light is not on
and the pump motor does not
operate.
The SOFT LED light is not on
and the pump motor does
operate.
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.
10.1 Troubleshooting for a hard reading
When the red LED is on continuously and the instrument measures hard water, do the steps that
follow.
Possible cause
No power
Problem with the power
supply
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 that the power switch is
set to on.
• Connect the power cord.
• Replace the fuses if necessary.
Replace the main circuit board.
Contact technical support.
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