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Van ’t Hoffstraat 12
2665 JL Bleiswijk, The Netherlands
T. 31 (0) 10 522 43 73
F. 31 (0) 10 521 19 41
E-mail: [email protected]
Website: www.tamson.com
VAT: NL 80 66 34 984 B01
Bank account no.: Rabobank 16 01 00 046
Chamber of commerce 27 16 95 41
IBAN Code: NL95 RABO 0160100046
Tamson Instruments bv
Rev. 2.1 UK 0517
7
Menu items
Use the turn-push button to select a menu item and
select the item by pressing the button. After pressing a
sign appears next to the value indicating the value can
now be changed. Pressing the button again activates
the value immediately. When the value is altered but the
button is not pressed the value will be accepted and
stored after 5 seconds automatically. The menu returns
back to normal operating mode.
7.1.1
Menu item "Set point"
Select the set point temperature. Resolution is 0.01°C +/-
the system accuracy.
There bath can be cooled down more rapidly by entering
the minimum set point of -40°C. Both compressors are
than switched-on and the systems cools down fastest.
When the bath has reached a temperature just below the
desired SP, set the new SP. For example if the bath is
running at 40°C and the operator wants to lower the
temperature to 5°C. Set the SP to -40°C. When the unit
has reached 4°C set the new SP to 5°C. The unit will than
heat and get stabilised around 5°C.
Care must be taken when using water as bath fluid as
there is a risk of freezing.
The reason for following this procedure is technical and is
caused by the way the cooling capacity is adapted over
the temperature span of the bath.
If the unit does not get stable, please have a look at the
PID parameters. These settings are explained in the
manual. Standard values are 25, 16 0. If the unit
fluctuates too much try to increase the P to 50 or 100 and
the I to 50.
To get stable temperature control with small variations is a
secure procedure and may take effort to realise.
7.1.2
Menu item "Offset"
The temperature displayed can be increased or
decreased with an offset ranging from +5.00 down to -
5.00 in steps of 0.01°C.
The offset will synchronise the bath temperature readout
with an independent separate thermometer.
If there remains an offset try to decrease the P down to 2
(instead of 25). The offset is due to the PID setting and
depends on the applied power percentage. When the
power percentage is below 15% the P value must be
lower than 25, i.e. 10.