EXTREMELY
ACCURATE, LOW-NOISE ANALOG MEASUREMENT
SYSTEM for
» 0-5v Sensors
» Low-Level Bridge Output Sensors
» 4 to 20 mA Sensors*
A switched 24-volt power supply provides
everything needed to operate 4 to 20mA
loop sensors.
KEY FEATURES - SUPPORTS THE FOLLOWING (one at a time only)
0-5 V SINGLE ENDED ANALOG INPUT
(General Purpose Analog Sensors)
0 to
(+/-)39 mV Differential Analog Input
(for BRIDGE TYPE PRESSURE SENSORS)
4-20
mA INPUT SENSORS (any type of 4-20mA
Sensor)
Also supports the following outputs:
2.5
V EXTERNAL VREF to support accurate references
for sensors.
SWITCHED BATTERY OUTPUT to
power sensors and conserve battery power
when not performing measurements
24 V
OUTPUT to power 4-20 mA CURRENT LOOP
SENSORS
Use Sutron’s Analog Stage
Discharge Recorder when a shaft encoder
cannot be used &/or when
there is no stilling well. This SDR comes
without a shaft encoder & can......
READ
A DIFFERENTIAL BRIDGE PRESSURE SENSOR
(resistive bridge output sensors like
Druck). The sensor, installed on the
bottom of water being measured, is connected
by terminal strip (provided) to the side
of the SDR enclosure.
READ virtually ANY
4-20 mA SENSOR either PRESSURE or ULTRASONIC
LEVEL (for example) as the source of
data for calculating stage discharge**.
READ
0 to 5V LEVEL SENSORS
The system functions
with input voltages as low as 5.5 V.
However, if the SDR battery is supplying
power
to external sensors, the low battery
operating point of the external sensors
applies. 12 VOLT BATTERIES ARE RECOMMENDED
FOR TYPICAL APPLICATIONS.
Software provides
additional slope & offset
fields to convert output information
to appropriate units.
**Note ONLY ONE SOURCE OF WATER LEVEL
DATA may be input at any one time to
calculate Stage Discharge
SPECIFICATIONS
Input
Voltage
8-16
Volts
Temperature
Range
-40° to +60° C
Temperature
Coefficient
10
ppm/c max
2.5
Volt Ref
+/-
10 mV
Switched
Battery
Short
Protected
Lightning
Protection
Sufficient
for most installations
SINGLE
ENDED
Number
of Bits
24
Full
Scale
0
to 5 Volts
Resolution
0.298 µV
Noise
(p/p) @25°C
6.5
µV (p/p)
Noise
(rms) @ 25°C
3.4 µV
RMS
Accuracy
@ 25°C
0.02%
Input
Impedence
<2M
Ohm
DIFFERENTIAL
Number
of Bits
24
Full
Scale
+/-
0.0390625 V
Resolution
4.657 µV
Noise
(p/p) @25°C
1.6
V (p/p)
Noise
(rms) @ 25°C
0.38 µV
Accuracy
@ 25°C
<0.01%
Input
Impedence
>3M
Ohm
FLOAT
WHEELS
Operates
with these diameters: 18 inch, 375
mm, 1 foot.
4-20mA
INPUT
Number
of Bits
24
Full
Scale
20
mA
Resolution
<1
mA
Accuracy
@25° C
0.02%
24
Volt Current Loop Power
24
Volt +/- 5%
24
Volt
Short
Protected
ORDERING
SDR-0001-3 SDR w/Analog Input & 4-20mA outputs
The Analog Stage Discharge Recorder does not include a shaft encoder, which is ordered separately.
SDR-0001-4
SDR w/Analog Input, 4-20mA outputs, & shaft encoder
Includes a shaft encoder
RECOMMENDATIONS
1. Stilling well with minimum 8” diameter
2. 5/16” shaft float wheel/pulley
with circumference of 12”, 18”, & 375mm.
If the float wheel does not have an insulating
hub, a PVC float must be used. (See Ordering
Options)
3. Beaded wire/tape compatible with the
float wheel.
4. Float/ counterweights.
5. 12-volt alkaline battery with capacity
of at least 20 amp-hrs. (See Ordering Options).
