Chemtrac HydroAct 4, Руководство пользователя

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4. Outputs
Outputs are the means by which values from measuring sensors, control outputs or system status are
transmitted to another device. For example to a SCADA
1
for data acquisition or to a pump for dosing
control. The two types of output used by HydroAct 4 are the analog output
2
and relay
3
.
In order to utilize the full capability of the instrument it is necessary to link the signal/value and an
output device, such as an alarm, threshold or control options for the relays or analog outputs.
Chemtrac utilizes the latest in firmware and electronic innovations and as such analog outputs and
relays are extremely flexible, and are not tied to individual sensors. In the past outputs were typically
fixed to a specific sensor or control and the range was also the same as the range of the sensor.
More recently the capability of the analog output to be more flexible has come about with advances in
electronics.
4.1 Analog Outputs
4.1.1 General Information
Analog outputs are typically a current output varying between 4mA and 20mA (although other options
are available), and are proportional to a varying signal of interest generated by the instrument. Analog
outputs are installed by plugging in a small output board into one of the available slots. Other output
options in addition to 4..20 mA are shown below.
4.1.2 Technical Data
Supported modes 0..20mA, 4..20mA, 0..1V, 0..10V, 1..10V
Maximum voltage output 15V DC (0/4..20mA only)
1
Supervisory Control and Data Acquisition, a central data logging and control system
2
A current or voltage output, proportional to a signal generated in the instrument
3
A mechanical or electronic device mounted on the electronics within the instrument that can switch. The number and type of
relays is specified at the time of order