Analog Output - Hanna Instruments HI 22 Series Instruction Manual

ANALOG OUTPUT

All models HI 21XY1, HI 21XY3 and HI 22XY1 are provided
with the analog output feature.
The output is isolated and can be a voltage or a current.
With the recorder, simply connect the common port to the
ground output and the second port to the current output or
voltage output (depending on
which parameter is being used)
as depicted aside.
The type (voltage or current)
and the range of the output
analog signal is selectable through the jumpers on the power
board.
Configurations of the jumpers are as follows:
Output
0-5 VDC, 1-5 VDC
0-10 VDC
0-20 mA, 4-20 mA
0-1 mA
Choice between different ranges with the same configuration
(for example 0-20 mA and 4-20 mA) is achieved via soft-
ware by entering the setup mode and selecting code 40 (see
Setup Mode section for exact procedure).
Factory default is jumpers 1 and 3 closed (ON) and jumpers
2 and 4 open (OFF), i.e. 0-20 mA, 4-20 mA and 0-10
VDC.
In any case, contact the nearest Hanna Customer Service
Center for changing of the default configuration.
By default the minimum and maximum values of analog
output correspond to the minimum and maximum of the
range of the meter. For example, for the HI 21 series with a
selected analog output of 4-20 mA, the default values are
0.00 and 14.00 pH corresponding to 4 and 20 mA, respec-
tively.
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Jumper 1 Jumper 2 Jumper 3 Jumper 4
OFF ON – – – –
ON OFF – – – –
– – – – ON – –
– – – – OFF – –
These values can be changed by the user to have the analog
output matching a different pH range, for example, 4 mA =
3.00 pH and 20 mA = 5.00 pH.
To change the default values, the setup mode must be en-
tered. Setup codes for changing the analog output minimum
and maximum are 41 or 42, respectively. For the exact
procedure, refer to the setup mode section in the manual.
Note
The difference between maximum and minimum values for
the analog output must be at least 1.00 pH or 50 mV.
Note
The analog output is factory calibrated through software. The
user may also perform these calibration procedures following
the procedure at page 46. It is recommended to perform the
output calibration at least once a year.
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