Page 17 of 26
Hydra 798 Iss.10 – 04/18
UNITS
Momentary pressing the Scroll key will show the controller units °C or °F.
DIAGNOSTIC ALARMS
These indicate that a fault exists in either the controller or the sensor.
CONTROLLER ERROR MESSAGES
The instruments include powerful diagnostics and in the unlikely event of an internal failure, or a sensor error, one of
the following error messages may be displayed.
Display shows
What it means
What to do about it
EE.Er
Electrically Erasable Memory Error:
The value of an operator or configuration
parameter has been corrupted
Contact Isotech
S.br
Sensor Break:
Input sensor is unreliable or the input
signal is out of range.
Contact Isotech
Check rear panel to ensure
connection of both control and over-
temperature sensors
HW.Er
Hardware error
:
Indication that a module is of the wrong
type, missing or faulty
Contact Isotech
LLLL
Out of Display range, low reading
Contact Isotech
HHHH
Out of Display range, high reading
Contact Isotech
Err1
Error 1: ROM self-test fail
Consult Isotech
Err2
Error 2: RAM self-test fail
Consult Isotech
Err3
Error 3: Watchdog fail
Consult Isotech
Err4
Error 4: Keyboard failure
Stuck button, or a button was pressed
during power up.
Switch the power off and then on
without touching any of the controller
buttons.
Err5
Error 5: Input circuit failure
Consult Isotech
Pwr.F
Power failure
. The line voltage is too low
Check that the supply to the
controller is within the rated limits
