Hanna Instruments pH 500 Series, Инструкция по эксплуатации

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ANALOG OUTPUT
All models pH 500XY1 and mV 600XY1 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 switch are as follows:
Output Switch 1 Switch 2 Switch 3 Switch 4
0-5 Vdc, 1-5 Vdc OFF ON – – – –
0-10 Vdc ON OFF – – – –
0-20 mA, 4-20 mA – – – – ON – –
0-1 mA – – – – OFF – –
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 switches 1 and 3 closed (ON) and switches
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 out-
put correspond to the minimum and maximum of the range
of the meter. For example, for the pH 500 series with a se-
lected analog output of 4-20 mA, the default values are 0.00
and 14.00 pH corresponding to 4 and 20 mA, respectively.
IDLE MODE
During idle mode the device performs the same tasks as when
it is in control mode except for the relays. The alarm relay is
activated (no alarm condition), the acid and base relays are
not activated while the analog output remains activated.
When the instrument is in idle mode the red and green status
LEDs are on.
Idle mode is useful to disable control actions when the exter-
nal devices are not installed or when the user detects un-
usual circumstances.
Control actions are stopped as soon as
the user presses SETUP and enters the
password.
In order to reactivate the control mode, use code 02 of setup
(see “Setup” section). Otherwise, the meter remains in idle
mode.