Acuity AccuRange AR1000, Руководство пользователя

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AR1000 User’s Manual
Rev 1.7 1/10
21
6. Analog Output Operation (RB, RE, SE)
The analog output uses two wires. The output is Red and the return is Blue. The return wire is the
power supply ground. The current loop output is always on.
The analog output is updated with each sample measured. The analog output will deliver a current
which increases linearly from 4 mA at the range beginning point to 20 mA at the range end point.
Best accuracy and noise immunity is obtained by connecting a 500 Ohm resistor to the current return
wire at the measurement point. For connection details, see section 0
6.1. Setting the analog range beginning point (RB)
The default setting for RB is 1000 (1000 meters is beyond the allowable range of the AR1000)
The parameter units for RB are dictated by the scale factor (SF). See section 5.2.2
The RB, range beginning command, sets the location of the point that is assigned 4 milliamps in
the current loop output. The range beginning point can be set to any distance within the sensor’s
natural measurement range. RB may be greater or less than RE.
6.2. Setting the analog range end point (RE)
The default setting for RE is 2000 (2000 meters is beyond the allowable range of the AR1000)
The parameter units for RE are dictated by the scale factor (SF). See section 5.2.2 for
information about scale factors (SF).
The RE, range end , command sets the location of the range ending point sometimes referred to as
the end of the measurement range. The range ending point is assigned 20 milliamps in the current
loop output. The range ending point can be set to any distance within the sensor’s natural
measurement range. RE may be greater or less than RB.
6.3. Setting the Error Mode (SE0, SE1 or SE2)
The default setting is SE1
The AR1000 can be configured to output analog signals for special error conditions that
correspond to Error Messages E15, E16, E17 and E18 (See Error Messages section 5.3 for more
information).
SE0<Enter> will cause the AR1000 to output and hold the last valid measurement
SE1<Enter> will cause the sensor to output 3 mA if RE>RB and 21 mA if RE<RB
SE2<Enter> will cause the sensor to output 21 mA if RE>RB and 3 mA if RE<RB
The SE command also affects the Alarm output. See section 7.5