|
 The
Model 3530 LVDT Conditioner accurately measures displacement, force,
pressure, and other parameters obtained with a 5- or 7-wire LVDT
sensor or with a 3- or 5-wire variable reluctance transducer. Input
provisions exist for "long-stroke" LVDT's (see Specifications).
Working
on the synchronous carrier-demodulator principle, the 3530 supplies
nominal 3 VAC (rms) excitation for a single transducer input. It
then demodulates, filters, and amplifies the resulting signal to produce a
reading precisely proportional to LVDT core displacement. The 3530
automatically adjusts the signal phase shift of the transducer in use,
thereby insuring optimum sensitivity and linearity.
The
3530 offers all standard 3500 Series features,
including
 |
selectable
digital smoothing |
|
custom
15-segment linearization |
|
HI/LO
limit monitoring with logic I/O |
|
scalable
analog output |
|
analog
+peak capture |
|
automatic
tare offset |
|
digital
track and hold |
|
either single-node
(RS232) or multinode network (RS485) communications |
The
instrument can be completely set up and operated either through the
front-panel keypad or via simple mnemonic
commands received from an external computer or terminal through
the RS232/RS485 Interface Port.
For
typical 3530 operations, see the following
applications:
LVDT Conditioner Specifications [Top 
]
(Click
here for 3500 Series General
Specifications; see also
the statement
on Daytronic accuracy specifications)
|
|
Input
Type |
Series-opposed
5-, 6-, or 7-wire LVDT sensor or 3- or 5-wire variable reluctance transducer
capable of 3280-Hz operation and having primary impedance of 80
Ω or greater |
|
Input
Ranges (full-scale) |
"Normal":
0-150, 0-300, and 0-600 mV/V
"Long-Stroke": 0-1, 0-2, and 0-4 V/V |
|
Excitation
Supplied |
Nominal
3 VAC (rms) at 3280 Hz; 40 mA maximum |
|
Common-Mode
Range |
±5
V operating; ±12 V without instrument damage |
|
Common-Mode
Rejection Ratio |
Infinite
at DC and 60 Hz; -60 dB at 3 kHz |
|
Input
Impedance |
Normal-Mode:
400 kΩ
Common-Mode: 100 kΩ |
|
Offset |
Initial:
±0.25% of full scale
Vs. Temperature: ±20 ppm/°C
Vs. Time: ±10 ppm/month |
|
Gain
Accuracy |
±0.02%
of full scale ± 1 count LSD, typical, following calibration |
|
Gain
Stability |
Vs.
Temperature: ±50 ppm/°C
Vs. Time: ±20 ppm/month |
|
Analog
Filtering |
|
Fixed |
100
Hz |
|
Selectable |
5-pole
filter with selectable low-pass corner frequency of 5, 10, or 20 Hz |
|
Frequency
Characteristics |
|
Corner
Frequency |
| Response
at . . . |
5
Hz |
10
Hz |
20
Hz |
|
-3
dB |
5
Hz |
10
Hz |
20
Hz |
|
-60
dB |
32
Hz |
65
Hz |
125
Hz |
|
|
Step
Response Settling Time (Full-Scale Output) |
|
Corner
Frequency |
| |
5
Hz |
10
Hz |
20
Hz |
|
To
1% of final value |
250
ms |
125
ms |
60
ms |
|
To
0.1% of final value |
400
ms |
200
ms |
100
ms |
|
To
0.02% of final value |
600
ms |
300
ms |
170
ms |
|
|
Peak
Capture |
Positive
analog peak, digitally held for indefinite display; minimum full-scale
input pulse duration is 15 msec (to 1% of full-scale accuracy), 25 msec
(to 0.1% of full scale accuracy), and 35 msec (to 0.02% of full-scale
accuracy); PEAK and TRACK modes controlled by front-panel button, rear-panel
logic input, or computer-port command |
|
Analog
Output: See 3500
Series General Specifications |
|
Frequency
Characteristics and Step Response Settling Times |
After
(A) FIXED ANALOG FILTER and after (B) +PEAK in "PEAK" or
"TRACK" Mode: -3 dB at 100 Hz; -60 dB at 750 Hz; settling
time to 1% of final value: 15 msec; to 0.1% of final value: 25 msec; to
0.02% of final value: 35 msec After
(C) SELECTABLE ANALOG FILTER: See Analog Filtering
(Selectable), above |
|
