13
4
Controller
Full details are in the Cryojet Controller Technical Handbook, included together with this
manual. See also Figure 1.
4.1
Control of flow rates
The flow rates of the sample flow and shield flow are shown on the display in l/min (as if
they were measured at atmospheric pressure and 293 K). To change the flow to any value
from 0 to 10 l/min, hold down the SET button underneath the appropriate display and
press RAISE or LOWER.
4.2
Control of jet temperature
There are three modes of operation: Automatic, Manual and Heat Exchanger Off. The
light labelled “Heater” is on if the controller is in Automatic mode, or if it is Manual mode
with non-zero voltage supplied to the heat exchanger.
Automatic
In this mode, the temperature of the jet is controlled automatically.
To put the controller into Automatic mode, press the ON button on the left-hand side of
the front panel.
To display the Set Temperature press SET (left hand block of buttons) and keep it pressed.
To change the Set Temperature, hold down SET while using RAISE and LOWER.
To display the voltage being supplied to the heat exchanger at a given moment, press and
hold the ON button on the left-hand side of the front panel.
To select Automatic mode, the sample flow must be at least 2l/min. If a flow has been
selected but after a couple of minutes no flow can be felt, switch the heat exchanger
off
and see section 9.
Manual
In this mode, a fixed voltage is supplied to the heater in the heat exchanger. It is not
recommended for routine operation.
To select Manual mode, press MAN. The default voltage is zero.
To display the voltage supplied to the heat exchanger, press and hold MAN.
To change the voltage supplied, press and hold MAN, and use RAISE and LOWER.
Heat Exchanger Off.
In this mode, no voltage is supplied to the heater in the heat exchanger. This mode will
give the lowest possible temperature, but there will be some temperature variation.
To set this mode, press the OFF button on the left-hand side of the front panel.
