Adjusting The Safety Temperature Limit "Safe Temp" (Vers. Kt); Controlling The Medium Temperature Via Etc; Or Contact Thermometer (Vers. Kt) - IKA RH basic 2 Betriebsanleitung

Adjusting the safety temperature limit "Safe Temp" (Vers. KT)

Version RH basic KT/C and RH digital KT/C: The "Safe Temp" set screw (H) is to
the left of the "Temp" knob (E) on the front operator panel.
You can use the „Safe Temp" set screw (H) of the safety temperature limiter
to adjust the desired safety temperature. If the desired safety temperature is
exceeded by a higher adjusted target temperature, of if there is a defect in the
instrument controller, the heating turns off permanently in this state and the
stirring function continues to run at the speed that was set prior to the
malfunction.
• Using a straight-edge screwdriver, turn the "Safe Temp" adjustment screw (H)
as far as it will go clockwise (to the right).
• Do not turn the screw beyond the natural right or left limit of rotation, as this
will destroy the potentiometer.
• Use the "Temp" turn dial (E) to adjust the set-point temperature to desired
safety temperature ("Safe Temp").
• Turn the "Safe Temp" set screw (H) slowly to the left until the heating function
switches off and the signal light (I or J) goes off.
Wait for about one more minute to ensure that the signal light ( F ) going
off does not merely indicate the end of a switching cycle of the heater. If
the signal light (I or J) turns on again within this time, you must repeat the
procedure, slowly turning the "Safe Temp" (H) adjustment screw to the left
again.
When the signal light (I or J) does not light up again within one minute, the
safety temperature is correctly set.
• After this, turn set "Safe Temp" adjustment screw (H) back slightly to the right
(clockwise).
• After you have turned the unit switch (A) of and back on again, the device is
ready for operation.
NOTE: When the "Safe Temp" (H) adjustment screw is set to the minimum level
(as far as it will go to the left) the heating function is turned off.
Triggering of the safety circuit is shown in the following ways:
On the RH basic 2 and RH basic KT/C versions: the warning light (I) will flash
two times per second. (Note: regular flashing indicates that the safety circuit
has been triggered; this warning light remains permanently lit to indicate that a
standard heating cycle is in progress).
On the RH digital KT/C version: the letter "-S-" will be shown on the LED display
(G).
Controlling the Medium Temperature via ETC 1 or Contact Thermometer
The control of the medium temperature via ETC 1 or contact-thermometer
should be preferred. Its advantages are: just a short heating-up phase after
setting the rated temperature, practically no temperature drift and only a minor
temperature waviness.
The rear of the instrument houses the diode bushing for connection the ETS-D
or contact thermometer, or for plugging the contact plug.
The electronics of the instrument supply a test current that has to flow
over plug pins 3 and 5 of the diode bushing in order for the heating
plate to heat.
Safety contact thermometers
acc. to DIN 12 878 class 2 or acc. Gerstel are connected with a
three-wire cable, the test current flows through the contact thermometer.
Safety function
If the test current is interrupted because of e.g. breakage of contact
thermometer or falling out of the cable plug, the heating cuts off.
Contact thermometer without safety circuit
acc. to DIN 12 878 class 0. The instrument only heats if the test current circuit is
closed by an electrical connection of the plug pins 3 and 5.
15