Hach Lachat BD40HT, User Manual

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Fuse replacement
Fuses are not user-serviceable items. The need for fuse replacement in controllers indicates severe
technical failure and is therefore considered to be a service activity. If a blown fuse is suspected,
contact Technical Support.
Troubleshooting
Problems with the digestion block cause an alarm to sound and a safety message to show on the
controller display. The controller will no longer apply heat to the digestion block and it will start to
cool. Refer to
Table 5 .
After the problem is resolved:
• Push CONTINUE to clear the message and let it occur again if necessary.
• Push SUSPEND to disable the message until the system is powered off.
Table 5 Safety messages
Message Possible cause Solution
Overtemp. Protection–
Check Block Temp. The block is too hot when the sample
is added. Let the block cool to room temperature
before the next digestion starts.
The voltage switch on the back of the
block is on the wrong voltage setting. Change the voltage switch to the correct
setting.
An exothermic reaction has occurred. Make sure that the method in the controller
matches the written method. Repeat the
test.
18 English