Hanna Instruments HI 8000 Series - Manual (Page 66)

66
8 TROUBLE SHOOTING GUIDE
THE CONTROLLER DOES NOT FUNCTION
Check to insure that the proper voltage is applied to the controller. After con-
necting the controller to the power supply (wall outlet), the unit should initiate
and the Hanna logo should appear on the LCD. If this does not occur you
should check the main fuse located next to the power input connections. If chang-
ing the fuse does not solve the problem, call a Hanna Instruments Technical
Support.
The alarm led is on
This could indicate that the controller is attempting to open a valve (activate a
relay) on the PCB. This most likely is caused by a blown fuse on the PCB relay .
The alarm led is blinking
If the alarm led is blinking this indicates that a software alarm has occurred.
Check panel C25 (ALARM) to determine what type of alarm condition is active.
Mixing tank empty
Check water level in mixing tank. The controller will not function without a proper
water level in the mixing tank. Check the integrity of the tank and the water
supply lines.
pH sensor difference
This alarm is triggered if the difference between the real time values of the two
primary pH sensors exceed the specified maximum allowable difference. The
maximum allowable difference (offset) between pH sensor values can be custom-
ized using panel S55 (SENSORS CONFIG). If the alarm condition persists even
after corrective measures, check the calibration of each probe to insure proper
function.
EC sensor difference
This alarm is triggered if the difference between the real time values of the two
primary EC sensors exceed the specified maximum allowable difference. The
maximum allowable difference (offset) between EC sensor values can be custom-
ized using panel S55 (SENSORS CONFIG). If the alarm condition persists even
after corrective measures, check the calibration of each probe to insure proper
function.
pH sensor out of range
This indicates that the controller cannot adjust the pH value of the process within
the specified range. Check panel S40 (PH CONTROL) to insure the settings are
correct. Also you should check the pH tank and supply lines for proper level and
function. Check the pH level of the incoming water to determine if a change has