Vishay 2310B Instruction Manual

2300 SYSTEM

Signal Conditioning Amplifier

2310B

Oct 2009

Instruction Manual

Vishay Micro-Measurements

P.O. Box 27777

Raleigh, NC 27611

United States

Telephone [phone]

FAX [phone]

E-mail: [e-mail]

www.vishaymg.com

130-000137

INSTRUCTION MANUAL

MODEL 2310B

SIGNAL CONDITIONING AMPLIFIER

1.0 DESCRIPTION............................................................................................................................................................... 3

1.1 GENERAL........................................................................................................................................................... 3

1.2 SIGNIFICANT FEATURES .............................................................................................................................. 3

2.0 SPECIFICATIONS......................................................................................................................................................... 3

2.1 2310 SIGNAL CONDITIONING AMPLIFIER................................................................................................ 3

2.2 2350 RACK ADAPTER ...................................................................................................................................... 4

2.3 2360 PORTABLE ENCLOSURE....................................................................................................................... 4

3.0 CONTROLS .................................................................................................................................................................... 5

3.1 2310 FRONT PANEL.......................................................................................................................................... 5

3.2 2310 REAR PANEL ............................................................................................................................................ 6

4.0 OPERATING PROCEDURE ........................................................................................................................................ 7

4.1 SETUP AND AC POWER .................................................................................................................................. 7

4.2 GAGE INPUT CONNECTIONS ....................................................................................................................... 7

4.3 MILLIVOLT INPUTS........................................................................................................................................ 8

4.4 WIRING CONSIDERATIONS.......................................................................................................................... 8

4.5 OUTPUT CONNECTIONS................................................................................................................................ 9

4.7 FILTER OUTPUT SELECTOR ...................................................................................................................... 10

4.8 EXCITATION................................................................................................................................................... 10

4.9 AMPLIFIER BALANCE.................................................................................................................................. 11

4.10 BRIDGE BALANCE......................................................................................................................................... 11

4.11 BATTERY TEST .............................................................................................................................................. 11

4.12 GAIN .................................................................................................................................................................. 11

4.13 FILTER.............................................................................................................................................................. 12

4.14 DYNAMIC TESTING ...................................................................................................................................... 13

4.15 TAPE PLAYBACK........................................................................................................................................... 13

4.16 REMOTE-OPERATION RELAYS................................................................................................................. 14

4.17 QUARTER-BRIDGE NONLINEARITY........................................................................................................ 14

5.0 SHUNT CALIBRATION ............................................................................................................................................. 14

5.1 INTRODUCTION............................................................................................................................................. 14

5.2 SHUNT CALIBRATION COMPONENTS IN 2310....................................................................................... 15

5.3 SHUNT CALIBRATION — STRESS ANALYSIS......................................................................................... 15

5.4 TRANSDUCERS............................................................................................................................................... 16

5.5 STANDARD CALIBRATION RESISTORS .................................................................................................. 18

6.0 ACTIVE FILTER ......................................................................................................................................................... 19

6.1 FILTER CHARACTERISTICS ...................................................................................................................... 19

7.0 MAINTENANCE.......................................................................................................................................................... 20

7.1 ADJUSTMENTS ............................................................................................................................................... 20

7.2 BATTERY REPLACEMENT.......................................................................................................................... 22

7.3 COMPONENT REPLACEMENT................................................................................................................... 22

7.4 FUSE REPLACEMENT................................................................................................................................... 23

APPENDIX............................................................................................................................................................................ 23

WARRANTY ........................................................................................................................................................................ 24



Copyright Vishay Micro-Measurements, 1995-2009

All Rights Reserved.

Module with Stabilizer Accessory

Complete 10-Channel 2300 System

2310 Signal Conditioning Amplifier

2350 10-Channel Rack Adapter

4-channel System in 2360 Portable Enclosure

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1.0 DESCRIPTON

2.0 SPECIFICATIONS

1.1 GENERAL

The 2300 Series instruments comprise a versatile multi­channel system for conditioning and amplifying low-level
signals from strain gages (or strain gage based transducers)
for display or recording on external equipment. Each 2310B
Signal Conditioning Amplifier is separately powered and
electrically isolated from all others (and can be powered with
a separate line cord), although groups of amplifiers are
normally inserted into a multi-channel rack adapter or
portable enclosure.

The Model 2350 Rack Adapter accepts up to ten 2310B
Amplifiers for mounting in a standard 19-in (483-mm) rack;
the Model 2360 Portable Enclosure accepts up to four 2310B
Amplifiers for more portable use.

Each Model 2310B Amplifier incorporates precision high­stability bridge completion resistors and dummy gages, and
four shunt-calibration resistors, and is complete and ready for
use as delivered — only ac power is required via the Portable
Enclosure, Rack Adapter or separate ac line cord. Input and
output connectors are supplied with each amplifier.

1.2 SIGNIFICANT FEATURES

The 2300 Series is designed to provide features essential for
accurate stress analysis data in a broad range of measurement
applications. Principal features include:

• Fully adjustable calibrated gain from 1 to 11 000.

• Accepts all strain gage inputs (foil or piezoresistive),

potentiometers, DCDT’s, etc.

• Bridge excitation from 0.7 to 15Vdc (11 steps) plus 0.2

to 7 Volts continuously variable.

• Input impedance above 100 megohms.

• Two simultaneous buffered outputs: ±10V, ±1.4V (for

tape recorders).

• Wide band operation exceeding 60 kHz, -0.5 dB at all

gains and output levels.

• Four-frequency active 6-pole filter (10 to 10 000 Hz).

• Dual-range (±5000 and ±25000µ ε) automatic bridge

balance, with keep-alive power to preserve balance for
months without external power.

• Dual-polarity two-step double-shunt calibration.

• Optional remote calibration and auto balance reset.

• Playback mode to filter and observe or re-record

previously recorded magnetic tape data.

• And many other convenience features.

All specifications are nominal or typical at +23°C unless
noted. Performance may be degraded in the presence of
high-level electromagnetic fields.

2.1 2310B SIGNAL CONDITIONING AMPLIFIER

INPUT:

Strain gages: quarter, half or full bridge (50 to

1000Ω). Built-in 120Ω and 350Ω dummy gages;
1000Ω dummy capability. See Appendix, page 23.

Transducers: foil or piezoresistive strain gage
types; DCDT displacement transducers;
potentiometers.

EXCITATION:

Eleven settings: 0.7, 1, 1.4, 2, 2.7, 3.5, 5, 7, 10, 12

and 15 Vdc ±1% max. One variable setting : 0.2 to
7 Vdc

Current: 0-100 mA, min, limited at 175 mA, max.

Regulation (0-100 mA ±10% line change): ±0.5

mV ±0.04%, max measured at remote sense points.
(Local sense: -5 mV, typical, @ 100 mA, measured
at plug.)

Remote sense error: 0.0005% per ohm of lead
resistance (350Ω load).

Noise and ripple: 0.05% p-p, max (dc to 10 kHz).

Stability: ±0.02%/°C.

Level: normally symmetrical about ground; either

side may be grounded with no effect on
performance.

BRIDGE BALANCE:

Method: counter-emf injection at pre-amp;

automatic electronic; dual range; can be disabled on
front panel.

Ranges (auto ranging):

±5000µε (±1% bridge unbalance or ±2.5 m V/V),
resolution 2.5µε (0.0012 mV/V).

±25 000µε (±5% bridge unbalance or ±12.5 mV/V),
resolution 12.5µε (0.006 mV/V).

Balance time: 2 seconds, typical.

Manual vernier balance range: 100µε (0.050

mV/V).

Interaction: essentially independent of excitation
and amplifier gain.

Storage: non-volatile digital storage without line
power for up to two years.

SHUNT CALIBRATION:

Circuit (two-level, dual polarity): Single-shunt

(for stress analysis) across any bridge arm,
including dummy gage.

Double-shunt (for transducers) across opposite
bridge arms.

Provision for four dedicated leads to shunt external
arms.

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CAL circuit selected by switches on p.c. board.

Standard factory-installed resistors (±0.1%)
simulate:

±200 and ±1000µε @ GF=2 across dummy
half bridge;

±1000µε @ GF=2 across dummy gage (120Ω
and 350Ω).

±1 mV/V (double shunt) for 350Ω transducer.

Remote-operation relays (Option Y): four relays
(plus remote-reset relay for bridge balance and
relay for excitation on/off). Each relay requires 10
mA @ 5 Vdc, except excitation on/off 25 mA.

AMPLIFIER

Gain: 1 to 11 000 continuously variable. Direct-

reading, ±1% max. 10-turn counting knob (X1 to
X11) plus decade multiplier (X1 to X1000)

Frequency response, all gains full output:

dc coupled: dc to 125 kHz, -3 dB max.
dc to 55 kHz, -0.5 dB max.

ac coupled: 1.7Hz typ. to 125 kHz, -3 dB max.

Frequency response versus gain, full output:

GAIN

1-11 120 kHz 300 kHz

10-110 90 kHz 230 kHz

100-1100 70 kHz 150 kHz

1000-11000 55 kHz 125 kHz

Input impedance: 100 MΩ, min, differential or
common-mode, including bridge balance circuit.

Bias current: ±40 nA, typical max., each input.

Source impedance: 0 to 1000Ω each input.

Common-mode voltage: ±10V.

Common-mode rejection (gain over X100):

Shorted input: 100dB, min, at dc to 60 Hz;
90 dB, min, dc to 1 kHz;

350Ω balanced input: 90 dB, typical, dc to 1
kHz.

Stability (gain over X100): ±2 µV/°C, max, RTI
(referred to input).

Noise (gain over X100, all outputs):

0.01 to 10 Hz: 1 µV p-p RTI.

0.5 to 125 kHz: 6 µVrms, max, RTI.

FILTER:

Characteristic:

Low-pass active six-pole Butterworth standard.

Frequencies (-3 ±1 dB): 10, 100, 1000 and 10 000
Hz and wide-band.

-

0.5db

-

3 db

Outputs filtered: either one or both (switch-

selected on p.c. board).

AMPLIFIER OUTPUTS:

Standard output: ±10V @ 5 mA, min.

Tape output: ±1.414V (1 Vrms) @ 5 mA, min.

Linearity @ dc: ±0.02%.

Either output can be short-circuited with no effect
on the other.

PLAYBACK:

Input: ±1.414V full scale; input impedance 20 kΩ.

Gain: X1 to tape output; X7.07 to standard output.

Filter selection: as specified above.

Outputs: Both as specified above.

OPERATING ENVIRONMENT:

Temperature: 0° to +50°C.

Humidity: 10 to 90%, non-condensing.

POWER:

105 to 125V or 210 to 250V (switch-selected),
50/60 Hz, 10 watts, max.

Keep-alive supply (for bridge balance): Lithium

3.6V, 1/2AA or equal. Shelf life approximately
two years.

SIZE & WEIGHT:

Panel: 8.75 H x 1.706 W in (222.2 x 43.3 mm).

Case depth behind panel: 15.9 in (404 mm).

Weight: 6 lb (2.7 kg).

2.2 2350 RACK ADAPTER

APPLICATION:

Fits standard 19-in (483-mm) electronic equipment
rack.

Accepts up to ten 2310B Amplifiers. AC line
completely wired.

Wiring for remote calibration with Option Y.

POWER:

115 or 230 Vac switch selected in amplifiers, 50/60
Hz, 100 Watts max.

SIZE & WEIGHT:

8.75 H x 19 W x 19.06 D overall (222 x 483 x 484

mm).

13.5 lb (6.1 kg).

2.3 2360 PORTABLE ENCLOSURE

DESCRIPTION:

Enclosure to accept up to four 2310B Amplifiers.

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3.0 CONTROLS

AC wiring complete.

Wiring for remote calibration with Option Y.

POWER:

115 or 230 Vac switch selected in amplifiers, 50/60
Hz, 40 Watts max.

SIZE & WEIGHT:

9.06 H x 7.20 W x 18.90 D in

(229 x 183 x 480 mm)

6.75 lb (3.1 kg).

2310B Front Panel

The following functional descriptions are of a general
character for information only. The operating procedure is
covered in Section 4.0.

3.1 2310B FRONT PANEL

CAL Switches: Toggle switches to place shunt-

calibration resistors across arms of the input bridge.
“A” and “B” may simulate different input levels. (See

5.5 Standard Calibration Resistors for standard factory­installed resistors.)

OUTPUT Lamps: LED indicators which always
monitor the output. Primarily used to adjust AMP BAL
and check bridge balance. Fully lit with 0.04 volt at ±
10 V Output.

AUTO BAL Controls: The toggle switch has three
positions to control operation of the automatic bridge
balance circuit:

OFF (up) disables the circuit; the amplifier outputs
now represent true unbalance of the input bridge;
stored balance point is retained.

ON (center) enables the automatic bridge balance
circuit.

RESET (momentary down) triggers the automatic
bridge balance circuit to seek a new balance point.
(The prior stored balance point is replaced.)

The “HI” lamp (yellow LED) lights when the automatic
balance circuit is in its high range; it indicates a bridge
unbalance exceeding 1%. If the unbalance exceeds 5%
this lamp will cycle on and off continuously.

TRIM Control: A vernier control to refine bridge
balance when desired. Normally the automatic balance
circuit will achieve balance within several microstrain.

FILTER Buttons: Push buttons to reduce the upper
frequency cut-off (10 to 10 000 Hz) to reject undesired
noise during lower-frequency tests. Normally the “WB”
button would be depressed, achieving wide-band
operation (typically 125 kHz at –3dB).

The “IN” position of the “AC IN” button (alternate
action) ac-couples the amplifier thus eliminating the dc
component of the input signal. (However, modest
bridge balance is still required — see 4.14 Dynamic
Testing.)

EXCITATION Controls: The rotary switch selects the
desired bridge excitation. Most steps approximately
double the power dissipation in the bridge arms.

The toggle switch turns bridge power on or off. (Any
amplifier output in the OFF position is dc amplifier
offset, thermal emf from the bridge, or ac pickup in the
wiring.)

AMP BAL: A trimmer to adjust the amplifier balance
(EXCITATION should be OFF when this is adjusted).

- 5 -

GAIN Controls: Amplifier gain is the reading of the
10-turn control (1000 to 11 000) multiplied by the
selected push button (X1 to X1000).

The indicated gain is the gain from the input to the ±10V
Output. At the TAPE Output the gain will be lower by a
fixed factor of 7.07.

The 10-turn counting knob is equipped with a lock that
is engaged by pulling the lever away from the front
panel and then displacing it downward.

MONITOR Jacks: Three pairs of jacks accepting

0.080-in (2-mm) diameter plugs to monitor bridge
excitation (EXCIT), bridge output (SIG) and the
amplifier output (±10V). Except for ±10V return (black
jack), 10K resistors are in series with these jacks to
provide noise isolation.

BAT TEST: A momentary push button to check the
keep-alive batteries for the automatic bridge balance
circuit. (See 4.11 Battery Test.)

POWER Button: An alternate-action push button (and
LED indicator lamp) to turn ac power “on” and “off”.
(Bridge balance is retained even with POWER off or the
amplifier unplugged.)

3.2 2310B REAR PANEL

PLAYBACK Switch: The ON (up) position connects

the adjacent Tape Recorder INPUT coaxial BNC
connector to the input of the filter circuits (if selected on
the front panel) and post amplifiers. Full-scale input is
±1.4V. Both outputs are operable.

NOTE: This recessed switch must be returned to the
NORM position to monitor incoming signals at the
INPUT connector.

±10V Connector: A coaxial BNC connector for the
±10V Output of the amplifier. The ±10V Output is
typically connected to oscilloscopes, DVM’s, analog
multiplexers, etc.

TAPE Connector: A coaxial BNC connector providing
the output normally used with tape recorders. Full scale
is ±1.414V (1 Vrms for sine waves).

INPUT Receptacle: A 15-pin quarter-turn connector to
connect the input circuit to the 2310B. Quarter, half,
and full bridges, potentiometers, or voltage inputs can be
accepted simply by using the appropriate pins; see 4.2
Gage Input Connections for details. Mating plug
supplied.

NOTE: PLAYBACK switch must be set to the NORM
position to monitor incoming signals at the INPUT
connector.

POWER Connector: A male rack-and-panel connector
which supplies ac power in the instrument. Normally, it
engages with a powered connector in the rack adapter;
an individual line cord is available for servicing by
qualified technicians only; see paragraph 4.1e.

Prewired for remote operation of shunt calibration,
bridge excitation, and automatic bridge balance. [See

4.16 Remote-Operation Relay (Option Y).]

2310B Rear Panel

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4.0 OPERATING PROCEDURE

Prior to taking any readings with the 2310B, each FILTER
and GAIN push-button switch should be exercised several
times for best performance and stability.

4.1 SETUP AND AC POWER: Each 2310B Signal

Conditioning Amplifier has its own power supply and
may be operated as a freestanding unit (see paragraph

4.1e), or one or more 2310B’s may be inserted into the
Model 2350 Rack Adapter or the Model 2360 Portable
Enclosure.

CAUTION: Prior to removing or installing the 2310B
Amplifier or the 2331 Digital Readout into a rack
adapter or enclosure, the ac power cord must first be
unplugged. Refer system setup and all servicing to
qualified technicians. If the 2300 System is used in a
manner that is not in accordance with instructions and its
intended use, the protection provided by the equipment
may be impaired.

4.1a Turn off all 2310B Amplifiers before inserting

them into the rack adapter or cabinet; the red
POWER button should be in the “out” position,
protruding about 1/4 in (6 mm) from the panel.

4.1b Inside of each 2310B, between the rear panel and

transformer, set the AC LINE slide switch to the
nominal ac line voltage to be used (115 or 230V).

Also on the rear panel check that the recessed
PLAYBACK switch is at the NORM (down)
position.

4.1c Install the 2310B Amplifiers into the rack adapter

or cabinet, securing the thumb-screw at the bottom
of each front panel.

4.1d Plug the detachable line cord(s) into the appropriate

2350/2360 receptacle(s).

4.1e To power a freestanding 2310B for only

troubleshooting/servicing by qualified service
personnel, an individual power cord is required.

A non-CE-approved accessory line cord is
available from Vishay Micro-Measurements as part
number 120-001196.

4.1f The line cord should be plugged into an ac

receptacle which has a good earth ground for the
third pin.

NOTE: If the plug on the power cord must be
replaced with a different type, observe the
following color code when wiring the new plug:

Black or brown: High line voltage

White or blue: Low line voltage (“neutral” or
“common”)

Green or green/yellow: Earth ground

4.2 GAGE INPUT CONNECTIONS

It is suggested that the 2310B be turned on (press the red
POWER button) and allowed to stabilize while

preparing the input connectors. To prevent powering the
input bridge circuits at this time, turn the EXCITATION
rotary switch to 0.7V and the toggle switch to OFF.

4.2a Each amplifier uses a separate input plug, which is

supplied. Additional plugs are available from
Vishay Micro-Measurements (see 7.4 Component
Replacement) or from the plug manufacturer or
distributor. Suggested types:

Amphenol/Bendix PT06A-14-15 (SR)
ITT/Cannon KPT06B14-15P

These connectors are designed to MIL-C-26482
and may be available from other manufacturers. As
an aid to the technician, the pin arrangement for the
Input plug is shown in Figure 1.

Figure 1: Input Plug Pin Arrangement

4.2b The basic input arrangements are shown in Figure

2. Note that, except when using an external full
bridge, there must be a jumper in the input plug
connecting pins H and J; this connects the

midpoint of the internal half bridge to the S+
amplifier input. Precision 120Ω and 350Ω dummy
gages are provided in each Model 2310B. If using
a quarter bridge with resistance other than 120Ω,
350Ω, or 1000Ω, use circuit A2 in Figure 2. For
1000Ω quarter bridges, see Appendix.

4.2c When using an external full bridge (especially a

precision transducer), it may be desirable to employ
the remote-sense circuitry provided in the 2310B to
maintain constant excitation at the transducer
regardless of lead resistance. To enable this circuit,
open the right side-cover of the 2310B and raise the
small red SENSE switch to REMOTE (see Figure

4). Connect the sense leads between the transducer
and pins F and G of the INPUT plug as shown in
Figure 2, C2.

4.2d If it is desired to employ shunt-calibration across

one of the external bridge arms, additional wiring
is required to achieve maximum accuracy (see 5.0
Shunt Calibration for details). However, for half­or quarter-bridge inputs, shunting the internal
dummy half bridge or dummy gage is normally
recommended; neither of these circuits requires
additional wiring from that shown in Figure 2.

- 7 -