Thermo Scientific Orion Star A221
and Star A321 Portable pH Meter
Instruction Sheet
pH
English
Preparation
Power Source
1. Power adapter (sold separately)
a. Select the appropriate wall socket plug plate.
b Slide off the clear plastic cover from the plug plate.
c. Slide the plug plate into the groove on the back of the
power adapter.
d. Connect the power adapter to the meter and power
outlet.
2. Batteries (included with meter)
a. Select four AA alkaline batteries.
b. Confirm that the meter is powered off.
c. Remove the battery compartment cover – loosen the
screws holding the battery cover, release the top portion
of the battery cover from the meter (use a coin or your
finger) and release the bottom portion of the battery cover.
d. Orientate the batteries as shown in the battery
compartment housing and insert batteries.
e. Replace the battery compartment cover and screws.
Electrodes and Other Connections
1. Prepare the pH electrode and any other applicable electrodes according to the
directions in the electrode user guide.
2. Connect the appropriate items as labeled on the meter and as shown in the
figure above:
For additional information on meter setup and operation, refer to the reference guide.
The reference guide is on the included CD and available at
www.thermoscientific.com/water.
DO/
RDO
ATC/
COND
POWER
USB
RS232
REF
BNC
Remove screws
Orion Star A221 &
Star A321 Portable
Use coin
or finger
to lift.
