Solartron Metrology BICM Series Manual

BICM
(Boxed Inline Conditioning Module)
user leaet

Index
501651 Issue 13
Index
Section Title Page
Index . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.0 Introduction . . . . . . . . . . . . . . . . . 2
2.0 Technical Specification . . . . . . . . . . . . . . . 3
3.0 Operational and Set-Up Guide - BICM Kit . . . 6
3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . 6
3.2 Screen Connection . . . . . . . . . . . . . . . . . 8
3.3 Gain Adjustment . . . . . . . . . . . . . . . . . . . 10
3.4 Offset . . . . . . . . . . . . . . . . . . . . . . . . 10
3.5 Set Up Using Fixed Value Resistors . . . . . 11
3.6 Gain Set Up Procedure . . . . . . . . . 13
3.7 Offset Set Up Procedure . . . . . . . . . 14
4.0 The Case . . . . . . . . . . . . . . . . . . . . . . . . . . 16
5.0 The "Why Doesn't it Work Guide" . . . . . . 17
6.0 Application Notes . . . . . . . . . . . . . . . . . . . . 18
6.1 Transducer Installation . . . . . . . . . . . . . . . . 18
6.2 Example 1 . . . . . . . . . . . . . . . . . . . . . 22
6.3 Example 2 . . . . . . . . . . . . . . . . . . . . . 23
Return Of Goods
Solartron Sales Offices
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501651 Issue 13
1.0: Introduction & Glossary
The Boxed Inline Conditioning Module (BICM) is an electronics module that may be used with a wide range of LVDT transducers. Layout and size are
designed to allow the BICM to be easily fitted inline with the transducer cable and installed with the minimum of effort (or changed if ready connected to a
transducer)
The BICM output may be set for a full scale range up to ±10 VDC, offset facilities are provided. The BICM is either powered from a bipolar ±15 VDC supply
or a unipolar ±24 VDC supply depending on product type.
BICM - Boxed Inline Conditioning Unit
Gain - The output voltage per mm of transducer stroke
Offset - The output voltage when the transducer core is at null
P.C.B. - Printed Circuit Board
NPV - Nearest Preferred Value. A resistor selected from a standard range of value
(E24, E48, etc.) that is closest to the required value
BICM kits are supplied for user connection to an LVDT transducer.
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1.0: Introduction
2.0: Introduction

501651 Issue 13
Standard BICM IP67 BICM
Bipolar Supply Unipolar Supply Bipolar Supply
Power Requirement
Voltage ±15 V ±1.5 V 24 V ±2.4 V ±15 V ±1.5 V
Current ±15 mA nominal 30 mA nominal ±15 mA nominal
Transducer Excitation
Primary Voltage 2 Vrms nominal
Primary Frequency 15 kHz typical
Primary Current 10 mA nominal
Signal Input
Input Voltage Range Up to 2.5 Vrms
Input Load Resistance 100 kW
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2.0: Technical Specication
2.0: Technical Specication

501651 Issue 13
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Standard BICM IP67 BICM
Bipolar Supply Unipolar Supply Bipolar Supply
Signal Output
Voltage Output Up to ±10 V
Current Output 11 mA
Output Ripple <14 mVrms
Output Offset 100%
Temp Co. Gain <0.03% FRO / oC
Temp. Co. Offset <0.025% FRO / oC
Warm up Time 15 minutes recommended
Linearity 2(electronics only) <0.1% FRO
Bandwidth (-3 dB) 3250 Hz typical
1Other frequencies are available on request.
2The electronics has a specification of <0.1%, the overall linearity is dominated by the transducer.
3Other bandwidths available on request.
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2.0: Technical Specication
2.0: Technical Specication

501651 Issue 13
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Standard BICM IP67 BICM
Bipolar Supply Unipolar Supply Bipolar Supply
Environmental
Operation Temperature Range 0 - 70 oC
Storage Temperature Range -20 to +85 oC
IP Rating IP40 IP67
Mechanical and Connections
Connections Solder pad or factory fit Factory fit only
Enclosure Size 98.5 x 30.5 x 13.0 mm 73.0 x 20.6 mm
Weight 30 g 75 g
Material ABS 400 Series Stainless Steel
Cable Lengths
All specification limits assume a nominal 3 m cable length between transducer and BICM. The BICM can be mounted up to 10 m from the transducer, but
this may result in reduced performance. Not all transducers can cope with long cable lengths. Cable from the BICM to the processing unit or display should
be limited to 100 m.
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2.0: Technical Specication
2.0: Technical Specication

501651 Issue 13
3.1: Introduction
The BICM kit is supplied with a selection of potentiometers and an output cable allowing users to connect LVDT sensors and set up to their own
requirements. Connections are made to the BICM PCB as shown in Fig. 3.1A or Fig. 3.1B below depending on the PCB version.
The BICM output is adjustable for GAIN and OFFSET. See the specification for range of adjustments possible.
Gain is sometimes called span or range. This control will affect the output voltage at the full transducer stroke. Adjusting the control clockwise will increase
the output.
Offset is sometimes called DC shift or zero shift. This control may be used to zero the output if mechanically nulling the transducer is not convenient or
can provide as much as 100% offset to enable the output to be unipolar ie. 0V to 10 V for full transducer stroke. Adjusting the control clockwise will make
output more negative.
Adjustment is by means of trimmer potentiometers (also called variable resistor or pots). The BICM will accept fixed value resistors in place of
potentiometers.
The BICM is designed to accept the following types of potentiometer or resistor:-
Potentiometer - Standard 3/8in square top adjust type potentiometer, see Fig. 3.1 (ie. Bourns 3299 type). The BICM kit comes complete with four
potentiometers.
Resistors - 1/4W MRF4 style.
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3.0: Operational and Set-Up Guide - BICM Kit
3.0: Operational Guide

501651 Issue 13
Fig. 3.1A Connections to PCB - 105186 (Bipolar or Unipolar)
Fig. 3.1B Connections to PCB - 103766 (Bipolar only)
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3.0: Operational and Set-Up Guide - BICM Kit
3.0: Operational Guide
Yellow
SEC2
SEC1
Green
White
Screen
Primary
Blue
Red
I/O CONNECTIONS
PRI1
PRI2
Screen
VOUT
0V
-15 V
0V
+15 V
Power
Supply
Output
Signal
SEC2
SEC1
Green
White
Screen
Primary
Blue
Red
TRANSDUCER CONNECTIONS
I/O CONNECTIONS
PRI1
PRI2
Screen
VOUT
0V
-15 V
0V
+15 V
Power
Supply
Output
Signal
Yellow
White
Green
Blue
Red
0V (Signal
white
)
Secondary 2 Green
0V Supply
Green
+15 V Bipolar
+24 V Unipolar
Red
Vout Yellow
Gain Offset
R2
+R4
R3
-R4
RV2RV1
R2
R1
Secondary 1 White
Primary Exc 2 Red
Primary Exc1 Blue
-15V Bipolar only
Blue
Screen

501651 Issue 13
3.2: Screen Connection
The screen connection is arranged so that the transducer cable screen and I/O cable screen is connected and that some cable strain relief is
provided whilst setting up the board. Screens are not connected to 0V on the PCB. Screen and 0V may be connected on the PCB by using a wire
link or at the user connection end, for example at the PSU, but it all depends on the installation requirements.
Colours are for Solartron MACH 1 5 kHz Series transducers. Check individual transducer data sheets before connecting.
If a different polarity output is required secondary connections may be reversed. See application notes.
Centre Tap (CT), yellow wire, connection not required. Ensure no loose wires.
3.2 Screen Connection
Fit the potentiometers in the positions indicated in Fig. 3.3. The table below gives suggested values for use with some solartron LVDT's. Once fitted
the set up procedure can be followed to give the required output.
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3.0: Operational and Set-Up Guide - BICM Kit
FIG 4.2 SCREEN CONNECTION
3.0: Operational Guide

501651 Issue 13
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3.0: Operational and Set-Up Guide - BICM Kit
3.0: Operational Guide
TRANSDUCER POTENTIOMETER VALUE (ohms)
GAIN OFFSET
B2.5 100K 5K
B5.0 50K 10K
B10 100K 5K
B15 100K 5K
B25 100K 5K
B50 50K 10K
B100 50K 10K
Fig. 3.3 Component Installation
Top View
Side View
Fit this way round
FIG 5.1 COMPONENT INSTALLATION
Transducer
Connection
End

501651 Issue 13
3.3. Gain Adjustment
Gain adjustment is best done before offset adjustment. If an OFFSET potentiometer has been fitted then set this to the mid position.
GAIN SETUP PROCEDURE
1) Adjust the potentiometer to the approximate mid position, about 12 full turns from either end.
2) Adjust the LVDT core position to give 0V output.
3) Move the core to a full scale position either inwards (+ve output) or outwards (-ve output). Adjust the potentiometer value to give the required
full scale output voltage such as + or -10 V. Adjusting the control clockwise will increase the output.
4) Return the core to the null position and check the output. Repeat steps 2 & 3 as required.
3.4. Offset
Any offset required is set by simply adjusting the OFFSET potentiometer until the required positive or negative offset is achieved. Adjusting the
control clockwise will make the output more negative.
Example:- Output required is 0V to +8 V for full transducer stroke (fully out to fully in). Set the gain for an output of 0V ±4 V then apply an offset
of +4 V.
Applying the required offset can sometimes be difficult if the gain is not correctly set. The application notes may help.
If no offset is required it is best not to fit the OFFSET potentiometer.
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3.0: Operational and Set-Up Guide - BICM Kit
3.0: Operational Guide

501651 Issue 13
3.5. Set Up Using Fixed Value Resistors
Fit the components into the positions shown in Fig 3.4 once component values have been determined using the set up procedure.
The term nearest preferred value (NPV) is used throughout. This is a resistor selected from standard ranges (E24,E48 etc) that most closely
matches the value required.
Two resistors (in series) may be fitted to allow for more accurate calibration of gain and offset. If only one resistor is required a wire link is fitted
in place of the second resistor.
Gain adjustment is best done before offset adjustment. If an OFFSET potentiometer is fitted, set this to the mid position. If a resistor is fitted,
temporarily disconnect this.
If an offset is to be applied take this into account when setting the gain.
Example:- Output required is 0V to +10 V for full transducer stroke (fully out to fully in). Set the gain for an output of 0V ±5 V then apply an
offset of +5 V.
Some suggested start values for resistors are shown in the table below. If the transducer being used is not in the list then start with an arbitrary
value such as 50 Kohms.
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3.0: Operational and Set-Up Guide - BICM Kit
3.0: Operational Guide

501651 Issue 13
TRANSDUCER APPROXIMATE RESISTOR VALUE (ohms)
GAIN OFFSET (+ or -5V)
B1.5 85K 20K
B2.5 61K 13K
B5.0 40K 7K5
B10 70K 15K
B15 52K 11K
B25 51K 11K
B50 39K 7K5
B100 25K 4K3
Fig 3.4 Resistor Positions
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3.0: Operational and Set-Up Guide - BICM Kit
3.0: Operational Guide

501651 Issue 13
3.6. Gain Set Up Procedure
If this procedure is to be used to determine the value of potentiometer required perform up to step (6). The potentiometer value will be the NPV
greater than the resistor value determined.
1) Temporarily connect a variable resistance (such as a decade box) to the board as in
Fig. 3.5(a). Set the resistor to an initial value as shown in the table.
Fig 3.5 Temporary Resistor Connections - Gain
2) Move the core to a full scale position either inwards (+ve output) or outwards (-ve output). Adjust the potentiometer value to give the
required full scale output voltage such as + or -10 V.
3) Move the core to the full scale position. Adjust the variable resistor value to give the required full scale output voltage such as + or - 10 V.
4) Return the core to the null position and check the output. Repeat steps 2 & 3 as required.
5) If a single resistor is to be fitted, fit a NPV fixed resistor to position R1. Fit a wire link to position R2. If two resistors are to be used for a more
accurate calibration see step (6)
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3.0: Operational and Set-Up Guide - BICM Kit
Resistance
Box
Resistance
Box
(a)
(b)
3.0: Operational Guide

501651 Issue 13
6) Fit a NPV fixed resistor that is just below the value required to position R1. Reconnect the temporary variable resistor to position R2, see Fig 3.6(b).
7) Repeat steps 2 & 3, moving the core between the null position and the full scale position adjusting the variable resistor as necessary to achieve the
required output.
8) Substitute a NPV fixed resistor for the temporary variable resistor position R2.
3.7 Offset Set Up Procedure
It is assumed that the gain has been set up consistent with the overall required result.
1) Set the transducer core to the null position. If this cannot be determined mechanically then, with no OFFSET resistors connected, adjust the core
position for a 0V output.
2) Connect temporary SOT or variable resistors (leads to be kept as short as possible) as shown for the required polarity offset. Fig. 3.6(a) for a positive
offset and Fig. 3.6(b) for a negative offset.
Fig 3.6 Temporary Resistor Connections - Offset
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3.0: Operational and Set-Up Guide - BICM Kit
Resistance
Box
(a)
(b)
POSITIVE OFFSET
NEGATIVE OFFSET
Resistance
Box
3.0: Operational Guide

501651 Issue 13
3) Adjust the variable resistance until the required offset is achieved.
4) If a single resistor is to be fitted, fit a NPV fixed resistor to position +R4 or -R4 . Fit a wire link to position R3. If two resistors are to be used for a more
accurate calibration see step (5).
5) Fit a resistor with NPV that is just below the required value to position +R4 or -R4.
Re-connect the temporary variable resistor to position R3.
6) Repeat steps 1 & 3, moving the core between the null position and the full scale position adjusting the variable resistor as required to achieve the
required output.
7) Substitute the temporary variable resistor for a fixed resistor of the nearest preferred value.
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3.0: Operational and Set-Up Guide - BICM Kit
3.0: Operational Guide

501651 Issue 13
The BICM case comprises two identical halves which are simply clamped around the PCB and connecting cables. Four self tapping screws are used to
secure the halves together.
Please note each half has a step along the side. The case halves will only mate correctly one way round.
DO NOT OVER TIGHTEN THE SCREWS when reassembling the case.
The strain relief blades in each half of the case may be removed if not required.
If enhanced environmental protection is required it is recommended that a suitable adhesive/sealant is applied to all edges of the case before assembly.
A suitable potting agent may also prove effective.
Fig 4.1 Case Assembly
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4.0: The Case
4.0: The Case
Strain Relief
Blades

501651 Issue 13
This is not an exhaustive list of problems but may help cure some of more common problems.
FAULT CONDITION POSSIBLE CAUSE OF FAULT
NO OUTPUT Power supply
Is it connected correctly?
Is it turned on?
Is there at least ±13.5 VDC at the power supply pads of the bipolar or +21.6 V for unipolar BICM?
Transducer
Is it connected correctly?
Is the transducer functional (perform continuity tests)?
SUPPLY CURRENT HIGH Power supply (see NO OUTPUT)
Transducer
Core not in transducer?
Short on primary connection?
Short on secondary connection?
Is the transducer functional (perform continuity test)?
Is the primary drive to transducer correct (compare with specification)?
Output load
Is the output shorted or wrong load?
INSUFFICIENT OUTPUT Power supply
Is there at least ±13.5 VDC at the power supply pads of the bipolar or +21.6 V for unipolar BICM?
Is there a proper 0V connection?
Transducer
Is the transducer core able to move the required amount?
Setup
Is gain and offset set correctly?
Have the components been fitted properly (any dry joints)?
WRONG POLARITY OUTPUT Transducer
Secondary connection wrong way round (swap white and green wires).
Set up
Voltmeter/indicator connected wrong way round.
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5.0: The "Why Doesn't it Work Guide"
5.0: The "Why Doesn't it Work Guide"

501651 Issue 13
6.1. Transducer
The MACH 1 5 kHz Series range of Transducer coil assemblies are designed for protection against dust and water to IP66, making them suitable for use
in harsh environments. Designed to be rugged and yet still cost effective, these devices offer the Customer all the attributes associated with LVDT’s. A
variety of combinations and accessories are available as options.
6.1.1. Introduction
The MACH 1 5 kHz Series range of transducers operate on the LVDT principal, where movement of a core inside the transducer body is detected by a
differential change in output on two secondary coils, the primary coil(s) being energised by an appropriate AC signal. With the core in a central position,
the coupling from the primary to each secondary is equal and opposite and therefore cancel out, thus the resultant output voltage is zero. As the core
is displaced further into one secondary, its voltage increases proportionally and the other secondary voltage decreases, hence the output changes in
magnitude and phase in proportion to movement in either direction from null.
The red and white connections are in phase for inward movement (ie. towards the cable end).
The output signal depends on both core movement and energisation voltage and is expressed as a sensitivity in mV output / V energising / mm travel.
6.1.2. Installation
LVDT transducers generally are a reliable and proven technology that is well established in all areas of manufacturing and control industries. The majority
of the associated problems experienced with their application and use are totally avoidable, particularly if sufficient thought is given during the initial design
stages of equipment, to the positioning and clamping methods employed for these feedback elements.
LVDT’s being of inductive nature are susceptible to some degree to the influence of magnetic fields and therefore should be positioned well away from
electric motors, relays and permanent magnets, where this is not possible then magnetic shielding should be considered as an alternative.
Clamping of the coil assembly should be carefully considered, some example methods are shown overleaf. Ideally the body of the transducers should be
clamped centrally in a pinch or yoke type clamp, manufactured from a low conductivity, non-magnetic material, if this is not possible then the introduction
of a non-metallic bush between body and clamp is a preferred alternative.
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6.0: Application Notes
6.0: Application Notes

501651 Issue 13
6.1.2. Installation (continued)
Irrespective of clamping method care must be taken not to overtighten retaining screws as distortion of the body may prove damaging to the integrity of the
transducer and adversely affect the geometry of the installation.
If the LVDT is to be mounted on equipment subject to high ”g” then dependent on the direction of these forces, it may be advantageous to consider end to
end clamping in preference to over body clamping.
The magnetic core supplied with each transducer has been manufactured and heat treated to achieve the optimum magnetic performance, any subsequent
handling of the core which results in stress being imparted will render the calibration void, this includes overtightening of the core during installation onto its
carrier. Hand tightening and retention by means of a suitable thread locking anaerobic retainer is the recommended procedure.
6.1.3. Cores
The standard core supplied with each transducer incorporates an M4 x 0.7 x 12 mm deep female thread at both ends for mounting onto a carrier. An
alternative 6-40 UNF female thread is available as a standard option upon request.
6.1.4. Carriers
A standard length carrier is available for each model of transducer, manufactured from 316 stainless steel and incorporating an M4 x 0.7 x 10 mm long
male thread for attachment to the standard core and an M4 x 0.7 x 20 mm male thread for attachment to the fixture.
6.1.5. Guided Carrier
MOUNTING Normal mounting methods apply (see section 6.1.2. on Installation). Careful consideration should be given to alignment, the carrier must be
able to move freely within the transducer core. Side force should be kept to a minimal level.
MAINTENANCE: Check for free movement of the carrier when in the vertical plane. Lubrication is provided via an oilite bush which is impregnated with
molybdenum disulphide and in normal usage is maintenance free.
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6.0: Application Notes
6.0: Application Notes