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Laureate™ Analog Output Option
Isolated 0-10 V & 0-20 mA
analog outputs scaled to the readout
for digital panel meters, counters and remote displays
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 Features
- 0-20 mA or 4-20 mA plus 0-10 Vdc.
- Outputs linearized to
reading.
- ±0.025% resolution
- ±0.05% full scale
accuracy.
- Isolation to 250 Vac.
- Scale and offset via
front panel or RS-232, RS-485.
- 60 Hz
update rate.
- 12 V compliance at 20
mA.
- Output derived from
filtered or unfiltered signal input.
- Certified to UL
61010C-1 (UL Mark), EN 61010-1 (CE Mark), and RoHS.
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| Description
The Laureate analog output option board
provides an isolated 0-10 Vdc voltage signal to drive a chart recorder, plus an isolated
0-20 mA or 4-20 mA current signal for transmission to a computer or central control room.
This option is compatible with all Laureate meters and counters, and turns these into
highly accurate, sourcing, 4-wire transmitters. The output for thermocouples, RTDs and
custom curves is linearized to the displayed reading.
A 12-bit D-to-A converter provides
0.025% resolution and ±0.05% full scale accuracy (1 LSB). The update rate
for meters is a
fast 56/s at 60 Hz power or 47/s at 50 Hz power, as determined by the
meter. The analog output can track the
unfiltered signal for fastest response, or the digitally filtered signal for best noise
rejection.
Scaling of the output is easily entered via front panel pushbuttons or via
the serial digital interface. The displayed readings to produce the low and high analog
outputs may be set to any value from -99,999 to +99,999 for DPMs, or -999,999 to +999,999
for counters.
Both the current (0-20 mA or 4-20 mA) or voltage ( 0-10 V) outputs are
available at the same time, and the same scaling applies to both. The
selected output selected output is calibrated to ±0.05% accuracy, while
the non-selected output is only accurate to ±2%.
Isolation is provided by a separate on-board power supply, which is
powered by the meter. This supply can drive 20 mA of current into loads up to 600 ohms for
12 V compliance. Isolation to signal ground and power ground eliminates problems caused by
ground loops.
The addition of the analog output option turns Laureate temperature meters
into superb, isolated, linearized, 4-20 mA temperature transmitters with exceptional
accuracy and high-speed response.
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Specifications
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Electrical |
Power Source
Signal Source
Output Linearization
Output Levels
Compliance, 0-20 mA
Compliance, 0-10 V
Isolation
Accuracy, selected output
Output Nonlinearity
Output Resolution
Output Update Rate
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Provided
by meter
Filtered or unfiltered digitized signal
Linearized to display
0-10V, 0-20 mA or 4-20 mA, jumper-selectable
12 V ( 0-600 ohm load )
2 mA ( 5 kOhm min load
Safety-rated to 250V rms working, 2.3 kV rms per 1 min test
0.05% of full scale
< 0.025% of full scale
12 bits (0.025% of full scale)
17 ms (unfiltered DPM)
Gate time + 30 ms + 0-2 periods (counter rate meter) |
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Scaling |
Zero Output
Full Scale Output
Minimum Span |
-99,999
to +99,999 (DPM), -999,999 to +999,999 (counter)
-99,999 to +99,999 (DPM), -999,999 to +999,999 (counter)
150 counts |
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J4
Pin Assignments |
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| Application
Examples |
Driving a Strip-chart Recorder |
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The 0-10 V output capability of the analog output board is
ideal to drive a strip chart recorder. As for 4-20 mA, the 0-10 V output can be scaled to
the meter reading to highlight signal level changes in a range of interest. |
Use as an Isolated, Linearized 4-20 mA Transmitter |
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| 0-20 mA output capability turns Laureate
meters and counters into high-accuracy, high-speed, isolated 4-20 mA transmitters. The
output is linearized to the reading, a major benefit with thermocouple and RTD inputs. |
The 4-20 mA signal can be transmitted via
twisted pair wires to a control room for supervisory process monitoring and control.
Process meters in series with the signal can provide local readouts
where required. |
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