Notes for trouble-shooting for
LAUDA Thermostats with P - electronics
G/Therm/Service/Fehler/Fehlpe1.doc
- 04.12.98
page 2 of 4
Malfunction
Fault
Reason
Remedy
Setpoint Ts is not
adjustable but will
disappear
Operating error
Setpoint is determined by the
analogue input; see right side of
display L2: A
Switch off analogue input
Sound signal appears
when a button is pressed
Another function blocks the
keybord e.g.: programme runs;
RS 232 active; Parameter etc.
Leave the function or press ESC
(RS 232) (R appears on the right
side of display L2); Stop access
and press the button “Local”
Display:
”Tu – Cursor flashes”
acoustic signal switches
compressor off after 1
min.
Wrong input
Actual value is < = Tu, resp.
setpoint adjusted too close to
low-temperature switch-off point
Tu; bath temperature ( Ti) falls
below Tu
Set low-temperature switch-off
point (Tu) at a lower value
Display
”Out of range”
Wrong input
Tried to enter values being out
of admissible ranges; Ts,To,Tu
being out of operating temp.
Choose the right values taking into
consideration their limitations;
check bath liquid or configuration
after having switched on the unit
Programme input out of
operating temperature range of
the unit
Enter admissible values
Value for Xp, Tn, Tv above
199,9
Enter admissible values
Tu or To is not
adjustable;
“Out of range ”
Input values are outside of
temperature limits of the type of
unit or initialization does not fit
to the type of unit
Reinitialize type of unit:
(see operating instructions
“Maintenance”); may also return
Default-values
Display:
“T
A
”
(only for USH 400(/6)
Motor chamber temperature
> 55 °C
Surrounding temperature of the
part of the thermostat may be too
high ( see operating instructions
5.2.8)
Display:
↓↓↓↓
(only for USH 400(/6)
RUL and RUK)
Level too low
Fill in bath liquid ; (see operating
instructions 5.2.3)
Display:
↑↑↑↑
(only for USH 400(/6)
RUL and RUK)
Level in the vessel is close to
overflow;
heater switches off
Either reduce the amount of
thermal liquid or install an other
vessel
Attention: HOT !!!
Display:
“Upper limitation of oil >
limitation of unit”
(cancelled beginning with
software version 1.06)
Admissible working temperature
range of bath liquid exceeds
operating temperature range of
the unit
Bath liquid is accepted, no other
steps necessary; unit limitations
valid
Setpoint cannot be
selected by means of
keyboard
Check setpoint selection; see
right side of display L2;
P=Programme; A=Analogue;
R=RS 232
Switch setpoint selection to
I=Internal
Display:
“External fault – clock
stop!”
Clock does not run
RAM defective
Unit has to be switched on once
again; set date and time once
again; see operating instructions if
necessary replace RAM