Furness controls FCO432 User manual

Please read carefully before using.
Manufactured by:
Furness Controls Limited
Beeching Road, Bexhill, East Sussex, TN39 3LG, England.
Telephone [phone]
Email: [e-mail]
Web Site: http://www.furness-controls.com
FCO432
Differential Pressure
Transmitter
Users Guide

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FCO432 Users Guide Issue 1

FCO432 Users Guide Issue 1 Page
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Table of Contents
Table of Contents..................................................................................................................................3
Revision Record....................................................................................................................................4
Safety Notes and Recommendations..................................................................................................5
Introduction ...........................................................................................................................................6
General Description.............................................................................................................................6
Enclosure.............................................................................................................................................6
Installation .............................................................................................................................................7
Mounting..............................................................................................................................................7
Pneumatic............................................................................................................................................7
Electrical..............................................................................................................................................8
Commissioning ...................................................................................................................................11
FCS541 - 400 Utility Software.............................................................................................................12
General Description...........................................................................................................................12
Installation..........................................................................................................................................12
Software Details ................................................................................................................................12
Instrument Settings ............................................................................................................................14
Menu Structure..................................................................................................................................14
Menu Navigation................................................................................................................................15
Troubleshooting..................................................................................................................................22
Error Messages ...................................................................................................................................23
Calibration............................................................................................................................................24
Recalibration using Keypad...............................................................................................................24
Recalibration using the FCS541 Utility..............................................................................................25
Calculations.........................................................................................................................................26
Pitot Tube Calculations......................................................................................................................26
Laminar Flow Element Calculation....................................................................................................28
Applications.........................................................................................................................................29
Measuring Direct Pressure................................................................................................................29
Using a Laminar Flow Element .........................................................................................................30
Using a Pitot Static Tube...................................................................................................................31
Alternative Electrical Connections....................................................................................................32
M12 (4-pole) Electrical Connection ...................................................................................................32
DIN Electrical Connection..................................................................................................................32
DIN with External Zero ......................................................................................................................33
Specification........................................................................................................................................34
Dimension Drawings...........................................................................................................................35
Basic Instrument................................................................................................................................35
Pipe Mounting Kit ..............................................................................................................................35
Wall Mounting Kit...............................................................................................................................36

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FCO432 Users Guide Issue 1
Revision Record
Issue
Date
Summary of changes
1
26-11-18
First release

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Safety Notes and Recommendations
Please read carefully.
1. All electrical supplies to the equipment must be externally fused with an appropriately rated
fuse for safety.
2. Always unplug the equipment from the supply before carrying out any servicing.
3. The air supply must be turned off before carrying out any work on the pneumatic system.
4. The air supply must not exceed that specified on the instrument or in the Test Certificate.
5. If in doubt about any aspect of safety with the equipment then contact Furness Controls
BEFORE proceeding.

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FCO432 Users Guide Issue 1
Introduction
General Description
The FCO432 is a fully configurable, industrial differential pressure transmitter. The configuration must
be carried out using either the FCS541 Utility software and cable, or the optional built in keypad. The
pressure cell is based on the unique Furness Controls capacitive sensor of proven reliability. A
microcontroller is used to control all functions of stability, such as temperature correction and display
damping. The output can be scaled as a linear or rooted function to facilitate the use of Pitot Static
Tubes or other primary flow elements. The FCO432 is suitable for industrial applications of control,
measurement and monitoring.
Features include:
Optional large character LCD display or an OLED display
Linear or rooted (Square root by default) output.
10:1 range adjustment using the Model 400 series software or optional keypad.
Optional Configurations:
2-Wire 4 to 20mA Current output
4-Wire Isolated 4 to 20mA Current output
4-Wire Isolated Voltage output
0 to 1V, 0 to 2V, 0 to 5V, 0 to 10V,
1V, 2V, 5V or 10V
Remote Zeroing Function
Zero the FCO432 with an externally fitted button, or suitable electronic circuitry.
Auto Zeroing Function
Adjustable delay between 0.0 and 24.0 hours with 0.1 hour resolution. Available to instruments
with the necessary hardware option fitted.
Dual Relay Trip Outputs
Relays can be configured to trip at pre-defined levels, or within a pre-defined pressure band.
Available to instruments with the necessary hardware option fitted.
Typical applications include:
Combustion pressure measurement and control of industrial furnaces
Air pressure measurement and control of dryers, kilns and ovens
Air flow measurement in conjunction with pitot static tubes, orifice plates or venturi
Enclosure
The instrument is housed in an IP54 rated ABS enclosure.
Pneumatic connections (fitted as standard) are for Ø4mmID push on tubing.
Optional pneumatic connections are:
⅛” BSPP Female threaded adaptor
¼” BSPP Female threaded adaptor

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Installation
Mounting
The recommended mounting position of the FCO432 is with the pressure entry ports facing directly
downwards. This helps prevent the ingress of dust and liquid.
Due to the sensitivity of lower range instruments, they should not be mounted in areas where they will
be subjected to high vibration as this could cause spurious readings.
The enclosure has four mounting holes for M4 screws, accessible with the cover removed.
Pneumatic
All pipe-work should slope downwards from the instrument to allow self-draining.
When using the instrument to measure pressure at a single point with long pipe runs the reference
port should be piped in parallel, with the pipe left open at the process end.

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FCO432 Users Guide Issue 1
Electrical
The FCO432 is fitted with a M12 connector as standard. See the “Alternative electrical connections”
section at the end of this user guide for non-standard connector information.
M12 (5-Pole) Electrical Connection
Connector type: 5-Pole M12 female, Code A, shielded, straight, field installable connector with screw
terminals and a PG9 cable gland (suitable for cable Ø4 to Ø8mmOD).
The instrument can be supplied as one of three configurations. See the rating plate on the
inmstrument for identification.
Pin functions:
Connection diagrams:
Pin
Colour
4 to 20mA
Output
Isolated
4 to 20mA
Output
Isolated
Voltage
Output
1
Red
+24V
+24V
+24V
2
Green
GND
GND
GND
3
Blue
mA+
mA-
Vout-
4
Yellow
mA-
mA+
Vout+
5
White
Remote Zero
Remote Zero
Remote Zero
5

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5
Connector wiring
Assembly Note
Housing alignment tabs must
be fitted into the plastic
locating slots and not the
electrical terminals

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FCO432 Users Guide Issue 1
Relay Connections (Option)
Connector type: 5-Pole M12 female, Code B, straight, field installable connector with screw terminals
and a PG9 cable gland (suitable for cable Ø4 to Ø8mmOD).
The FCO432 can incorporate a pair of relays for triggering auxiliary equipment such as alarms.
Note the relays are supplied from the +24V on the power connector.
Pin functions:
Relay states are shown for the instrument switched off.
Relay contact ratings
2A @ 55Vac/30Vdc (non-inductive load)
Pin
Colour
Relay Contact
1
Red
NO1
2
Green
NC1
3
Blue
NC2
4
Yellow
NO2
5
White
Com
The relays do not feature
any contact suppression
5

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Commissioning
Make the electrical and pneumatic connections as recommended.
Turn on the power supply.
Configuration settings (such as range, display settings, etc.) may be changed using the FCS541 Utility
software & cable or the optional built in keypad. Refer to the Instrument Settings section in this guide
for further details.
Check that either the current or voltage measuring device being used is registering. If not, check the
supply voltage is within specified limits and inspect for poor connections.
After fixing the instrument in position, allow at least one hour before commencing the final
commissioning.
With no pressure applied, check the output is correct for zero input.
If not:
press and hold the zero button (indicated below)
or activate the remote zero (if fitted)
or enable the auto zero function (if fitted), the delay time may have to be temporarily set to
0.1hour
NOTE: if the auto zero valve is fitted, pressing either the zero button or the remote zero will
force an auto zero cycle.
The instrument is now ready for operation.
Zero Button
(If keypad not fitted)
Press & hold for 1
second
i
Zero Button
Press & hold for
1 second

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FCO432 Users Guide Issue 1
FCS541 - 400 Utility Software
General Description
The FCS541 400 Utility software will run on any Windows computer and provides an easy to use
interface for configuring or making calibration adjustment to 400 series instruments. The software
can communicate with instruments via an RS232 cable, or a USB cable.
Installation
USB-B Connection
The FCO432 is fitted with a Micro USB-B connector on the main circuit board and can be fitted
with an optional external USB-B port.
USB drivers and support tools are available on the Furness Controls product CD (\Drivers\USB
drivers) or may be downloaded from http://www.furness-controls.com/filelist.
Optional RS232 Connection
If the FCO432 has an optional external RS232 port, a null modem cable will be required.
Software Requirements
The minimum requirement to run the software is:
Operating System: Microsoft Windows XP or above
Hard Disk: 4MB free space
Communications Port: One RS232 port or USB port
CDROM drive: For software install
Installation Procedure:
1. Download the FCS541 utility from the Furmess Controls download site
2. Double click the Setup.exe file
3. In the first instance the setup program will determine whether your system files need
to be updated
4. When the first stage has finished, Setup will notify you whether your computer needs
to be re-started for the new files to be registered. Click YES to proceed
5. After the computer has been restarted follow steps 1 to 3 again
6. Now Setup will guide you through the process of installing the application. It will ask
you for a location to install to and information regarding the Start Menu details.
Follow the instructions on screen
7. Once installed there is no need to re-start again and you should be able to start the
application by clicking on the FCS541 400 Utility icon in the Model 400 Utility
program group
Software Details
Set Custom Values
The software will always start on the Set Custom Values tab and this is the main screen for
accessing the user settings of FCO432 transmitter.
When the software runs, it will attempt to detect the current RS232 Port and Baud rate setting for
the connected transmitter. The communications baud rate can then be changed if necessary by
selecting a new baud rate from the drop-down list.
To the bottom right is a setting for the Fbus ID number. Although the 400 Series Utility software

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does not support Fbus functionality, it does however allow you to assign an ID number.
If the settings of the connected transmitter need to be viewed or altered, click on the Read from
Tx button. The Custom Units, Decimal Pnt., Display Low, and Display Hi boxes will only show
settings if Display is set to either Custom Units or Sqr. Root. If Display shows Eng. Units then
these four boxes are inactive and will be greyed-out.
The Relay Settings will only be active and show valid settings if the connected transmitter
incorporates relays.
Once all changes have been made, the new settings can be downloaded to the transmitter by
clicking on the Write to Tx button.
View Display
The View Display tab selects a screen where the display reading, as defined on the Set Custom
Values screen, can be viewed.
Click on the Start button to begin viewing the display reading, clicking on the Stop button will end
viewing of the display reading. To zero the transmitter display, click on the Zero Tx button.
Test a Device
The Test a Device tab is where test levels can be viewed.
By clicking the START button and setting the pressure ports to equal, Internal Pressure will show
the transmitters internal raw ADC reading and should be between -25000 and +25000 for a
working instrument with no pressure applied. When pressure is applied, this value should be
capable of showing between -5500000 and +5500000.
Please make sure the transmitter has stabilised at 20º when doing these tests.
The Internal Temperature should show a value of between 0 and 7000 for a working instrument.
At room temperature this value to be somewhere around 3000.
The Electrical Output test buttons allow the output level of the transmitter to be tested, regardless
of input pressures. A slider can be moved to the following 3 settings:
Minimum output set to the minimum value (e.g. 4mA).
Mid output set to the middle value between the minimum and maximum (e.g.12mA).
Maximum output set to the set maximum value (e.g. 20mA).
If the transmitter is fitted with relays or Auto Zero Valve, they can also be switched on and off
using this screen (ignoring the set trip points).
Clicking on the Reset Outputs button immediately cancels any of the tests.
Load and Save
The Load and Save tab allows settings to be saved or loaded from a file.
The Save to file button allows the user to enter a file name and location to save instrument
settings.
The Load from file button selects a file to load previously saved settings. Subsequent clicking on
the Write to Tx button downloads these settings to the connected transmitter.
Write Settings
The write settings tab allows the settings to be saved to text (.txt) file and formatted with each heading
and the setting that has been applied to it.
The Write settings button will save all the Transmitter settings under the headings from the 400
Series firmware menu.

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FCO432 Users Guide Issue 1
Instrument Settings
Menu Structure
┌
Main Screen
├
Pin
├
Set Pin
├
Filter
├
Display
├
Units
├
CST Unit
├
DP Low
├
DP High
├
DEC PNT
├
DSP Low
├
DSP High
├
Relays
│
├RL1 FUNC
│
├RL1 ON
│
├ RL1 OFF
│
├ RL1 DLY
│
├ DISP RL1
│
├ RL2 FUNC
│
├ RL2 ON
│
├ RL2 OFF
│
├ RL2 DLY
│
└ DISP RL2
├
AZ Delay
├
Z. Lock
├
Purge
├
Test
├
Comms
│
├ BAUD
│
└ Flash
├
User LIN
│
├ Point 1…5
│
└ % Adj 1…5
├
F. Level
├
Version
├
Serial
└
Unit ID

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Menu Navigation
The instrument settings are accessible via the four-button keypad on the front panel. For
instruments with no keypad, the FCS541 Software and cable are required.
Esc/Zero Escapes back through the transmitters menus until you return to the main
display reading.
When on the main display reading, holding this button for 2 seconds will zero
the pressure value. Unless the unit has an auto-zero option fitted, it is important
that no pressure is applied when doing this, otherwise the unit will give a false
reading.
Enter Confirms the data entry.
Up Steps through the menu structure and increments numerical data.
Down Steps through the menu structure and decrements numerical data.
The menu system can be accessed by pressing the or button. The and buttons step
through the menu, pressing from the menu will show the settings for the menu item displayed.
Pressing or buttons change numeric values by one digit. If either button is held for ten
seconds, the next decade will change by one digit. This continues up to a maximum setting of
1000.
Pressing twice will reset the and to alter the first digit.
A further press of the button will place the data in memory and return to the main menu.
If no button is pressed for 20 seconds the display will revert back to the main menu and back to
the normal display another 20 seconds after that. To return immediately to the normal display
press the or key until the display is shown or press the to exit the menu.
PIN
Purpose: A security code must be entered before the menu system can be accessed. The
factory setting is 0000, which disables the PIN function. If a code has been set then
the operator will be prompted for a PIN number when any key is pressed.
Setting a PIN number will also disable the zero button.
Options: Use any four-digit number between 0000 and 9999, using the and buttons to
set the required code.
NOTE: If the correct PIN number has been entered and no buttons are pressed for 20
seconds, the display will revert to the main display and the PIN number will
have to be entered again to allow further access to the menu.
SET PIN
Purpose: Sets the PIN security code
Options: Press the and buttons to select a number, and the button to store the
number.
NOTE: Set a value of 0000 to disable PIN security function.
FILTER
Purpose: Dampens the transducer response to reduce fluctuations when measuring turbulent
flows.
Options: 0.0 to 60.0 seconds
Filter considerations:
There are three factors that affect the response time of the output signal for a step
change in input pressure.

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FCO432 Users Guide Issue 1
1. Transmitter response time:
The design of the transducer and circuit has a natural response time of 20ms. This is
the time that a step change in pressure will cause a 63% signal change. A time of
100ms would give a signal change of 98%.
2. Output update frequency:
The transmitter uses digital conversions to temperature compensate and linearise its
output and because of this, the output signal is only updated every 50ms.
3. Software filter time:
The transmitter software generated filter (above) can be set from zero to 60 seconds
in 1/10 second increments. This is an applied time constant e.g. a value of 1 second
will apply a time constant of 1 second. The time-constant is the time taken to output
a signal equal to 63% of an input pressure change. A time of 5 seconds would give a
signal change of 98%This filter can be disabled by setting it to zero.
Display
Purpose: Sets the display to show engineering units, custom or square root functions.
Options: STD, CUST, ROOT
STD Displays the output in engineering units as set in the Units menu
CUST Display can be set to read almost any figures required, the most
common being 0-100% or 4-20mA. The display limits should be set
using the Custom Units, DP Low, DP High, Decimal Point, Display Low
and Display High menus.
ROOT Activates the root function. Both the display and output will be affected.
This should be used to obtain a linear output when using devices such
as Pitot tubes. The display limits should be set using the Custom Units,
DP Low, DP High, Decimal Point, Display Low and Display High menus.
By default, root 0.5 (square root) is set, but for exceptional cases, this
value can be set to any root between 0.15 and 0.95.
MATCHED Activates the user linearisation mode which can be used to correct for
non-linearity found when measuring the DP from a flow element. The
DP Low, DP High, DS Low, DS High should be set to your flow
elements calibrated scaling. Refer to the 400 series Flow Match section
within the Model 400 Configuration Utility on how to perform this type of
linearisation.
UNITS
Purpose: Alters the display to read in pre-calibrated engineering units.
Options: PA, KPA, MB, MM, IN, HG, IHG, BAR, PSI (Range dependent - see below)
50Pa to 30kPa instruments
1Bar to 10Bar instruments
Unit
Description
Unit
Description
0
PA
Pascal
BAR
Bar
1
KPA
Kilo Pascal
KPA
Kilo Pascal
2
MB
Millibar
MB
Millibar
3
MM
Millimetre H2O gauge
PSI
P.S.I.G.
4
IN
Inches H2O gauge
IN
Inches H2O gauge
5
HG
Millimetre Hg
HG
Millimetre Hg
6
IHG
Inches Hg
IHG
Inches Hg

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CST UNIT (Custom Units)
Purpose: Sets up a user defined unit display. Can only be used when the Display Menu is set
for CUST or ROOT. A variety of engineering units can be set.
Note: These are just display labels and use the menu functions DSP LO, DSP
HIGH and DEC PNT to control the displayed value.
Options: PA, KPA, MB … CCM, CCH (33 options as listed below)
Unit
Description
Unit
Description
0
PA
Pascal
18
CFH
Cubic Feet per hour
1
KPA
Kilo Pascal
19
CMS
Cubic Metres per second
2
MB
Millibar
20
CMM
Cubic Metres per minute
3
MM
Millimetre H2O gauge
21
CMH
Cubic Metres per hour
4
IN
Inches H2O gauge
22
LBS
Pounds per second
5
HG
Millimetre Hg
23
LBM
Pounds per minute
6
IHG
Inches Hg
24
LBH
Pounds per hour
7
PSI
Pounds per square inch
25
KGS
Kilograms per second
8
M/S
Meters per second
26
KGM
Kilograms per minute
9
MPH
Miles per hour
27
KGH
Kilograms per hour
10
F/S
Feet per second
28
MA
Milliamps
11
F/M
Feet per minute
29
PC
Percent
12
KMH
Kilometres per hour
30
SPACE
Units not displayed
13
L/S
Litres per second
31
CCS
Cubic Centimetres per second*
14
L/M
Litres per minute
32
CCM
Cubic Centimetres per minute*
15
L/H
Litres per hour
33
CCH
Cubic Centimetres per hour*
16
CFS
Cubic Feet per second
17
CFM
Cubic Feet per minute
Press the and buttons to select a number, if no more buttons are pressed the cursor will
move to the next digit, press the button to enter the number. If a number is entered by mistake
exit the menu and try again (do not return to the display).
DP LOW (Differential Pressure Low Output)
Purpose: Alters the differential pressure corresponding to the minimum output level.
The value can be set anywhere within the range of the instrument. The display will
be in the current engineering units selected.
Options: Any differential pressure value within the display or instrument range.
DP HIGH (Differential Pressure High Output)
Purpose: Alters the differential pressure corresponding to the maximum output level.
The value can be set anywhere within the range of the instrument. The display will
be in the current engineering units selected.
Options: Any differential pressure value within the display or instrument range.
DEC PNT (Decimal Point Position)
Purpose: Alters the position of the display decimal point if the display option is set to CUST or
ROOT.
Options: NNNN, NNN.N, NN.NN, N.NNN or .NNNN
DSP LOW (Display Low Reading)
Purpose: Alters the display value corresponding to the minimum output level. Can be set to
any numeric value within the range of the display. For instance, to display mA set the
value to 4.00. For %, set this value to 0.
Options: Any numeric value shown on the display
DSP HIGH (Display High Reading)
Purpose: Alters the display value that corresponds to the maximum output level. Can be set to
any numeric value within the range of the display. For instance, to display in mA set
the value to 20.00. For %, set this value to 100.
Options: Any numeric value shown on the display

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FCO432 Users Guide Issue 1
Relay Settings
Purpose: This sub menu contains various settings used for configuring instrument Relays.
RL 1/2 FUNC (Relay 1 & 2 Function)
Purpose: Alters the operational function of the relay.
Options: HYST, BAND
HYST Relay levels control the hysteresis for the switching levels.
BAND The relay operates between the levels to provide a pass-band function.
RL 1/2 ON (Relay 1 & 2 Set Level)
Purpose: Alters the display reading at which the relay will change to the ON state.
Options: Any value within the limits set by DSP HIGH and DSP LOW.
RL 1/2 OFF (Relay 1 & 2 Reset Level)
Purpose: Alters the display reading at which the relay will change to the OFF state.
Options: Any value within the limits set by DSP HIGH and DSP LOW.
RL 1/2 DLY (Relay 1 & 2 Delay Level)
Purpose: Alters the delay time (in seconds) before the relay goes into its de-energised state.
Options: 0 to 250 seconds.
DISP RL 1/2 (Relay 1 & 2 Display Alarm)
Purpose: Selects the condition that causes a visual alarm to be displayed momentarily and
repeated at regular intervals on the FCO432’s display.
Options: NONE, RESET, SET
NONE No Alarm message displayed for relay
RESET ALARM xx message displayed for Failsafe Operation
SET ALARM xx message displayed for Non-Failsafe Operation
Note: xx = 1 for Relay 1 only, 2 for Relay 2 only, 12 for Relays 1 and 2.
Relay Trigger Level Rules
Relay state changes are suspended when in the menus or setting parameters.
For fail-safe operation, the relay off state should indicate the fail or alarm condition.
There are two types of relay operation. HYST and BAND.
HYST:
1. If the relay set and reset levels have a different sign the positive level will be considered to
be the greater.
2. If the relay set and reset levels are both negative the magnitude is used to determine which
is greater.
e.g. more negative is greater
3. For the relay set level being greater than or equal to the relay reset level the relay state will
change to on as the reading rises to the set level and will remain in the on state until the
reading drops to the reset level when the relay state will change to off.
4. For the relay set level being less than the relay reset level the relay state will change to off
as the reading rises to the reset level and will remain in the off state until the reading drops
to the set level when the relay state will change to on.
5. The former mode of operation will provide fail-safe operation if signalling of a drop below a
minimum reading is required. The latter mode of operation will provide fail-safe operation if
triggering of a rise above a maximum reading is required. That is, in the event of either an

FCO432 Users Guide Issue 1 Page
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instrument or relay power failure the relay state will change from the normal on state to off,
indicating a fault condition.
6. If the relay set level is equal to the reset level and they are positive the relay will change to
its on state when the displayed reading is one least significant digit greater than the set
level and it will change to its off state when the displayed reading is equal to the reset level.
e.g. Level set to 5.00, relay will change to on state as reading rises to 5.01, relay will
change to off state as reading drops to 5.00.
7. If the relay set level is equal to the reset level and they are negative the relay will change to
its on state when the displayed reading is equal to the set level and it will change to its off
state when the displayed reading is one least significant digit greater than the reset level.
e.g. Level set to -5.00, relay will change to ON state as reading drops to -5.00, relay
will change to OFF state as reading rises to -4.99.
BAND:
1. If the relay set and reset levels have a different sign the positive level will be considered
to be the greater.
2. If the relay set and reset levels are both negative the magnitude is used to determine
which is greater. e.g. more negative is greater
3. For the relay set level being greater than or equal to the relay reset level the relay state
will change to on for any signal between the reset and set level. The relay will be off for
signals above the set level or below the reset level.
This provides a fail-safe relay when low or high pressure is the fault condition.
4. For the relay set level being less than the relay reset level the relay state will change to
off for any signal between the reset and set level. The relay will be on for signals above
the reset level or below the set level.
This provides a fail-safe relay when pressure between the set and reset levels is the fault
condition.
AZ DELAY (Auto Zero Interval Time)
Purpose: Alters the Auto Zero interval time (in 0.1 hours). This is the interval time after which
the instrument will automatically zero itself providing the optional hardware has been
fitted. Setting this value to zero will disable auto zeroing.
Options: 0.0 to 24.0 hours.
Auto Zero function
If the Automatic Zero function is fitted, this will allow the instrument to be re-zeroed without the
need to remove the applied pressure. The zero can be on a timed interval, triggered from the
remote input or the local zero button.
When the Automatic Zero cycle is triggered, the instrument freezes its display and output while
isolating itself from the +ve pressure port and connects both ports of the internal pressure sensor
to the -ve pressure port.
The circuit then samples this value and calls it zero pressure, then re-connects the sensor to the
+ve pressure port.
Once the sensor is re-connected, the display and output are updated with new readings.
The process takes approximately 1.5 seconds. If the supply voltage is not available to operate the
valve, the instrument displays the Error 4 message and goes into a fault mode until the problem
is corrected.
Z. LOCK (Remote Zero disable)
Purpose: Used to prevent users from manually zeroing the transmitter. When the Zero Lock is
on, any attempt to zero the device using either the zero button, remote zero signal,
or a zero command through serial comms, will be ignored.
Options: OFF, ON
OFFManual auto-zeroing can be performed
ON Manual auto-zeroing is prohibited.

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FCO432 Users Guide Issue 1
PURGE (Purge Duration)
Purpose: Defines an additional purge time that is used to vent any residual pressure from the
unit.
Options: 0.0 to 23.0 seconds
TEST
Purpose: Sets the output to a pre-set value. This feature can be used for test purposes.
Options: NORM, MIN, MID, MAX
NORM The output is a direct reading of the applied pressure (normal operation)
MIN The output is set to the minimum output level, e.g. 4mA
MID The output is set to mid output level, e.g. 12mA
MAX The output is set to maximum output level, e.g. 20mA
COMMS (Communications)
Purpose: This menu contains various settings used for serial communications.
BAUD (Baud rate)
Purpose: To set the communications Baud rate.
Options: 2400, 4800, 9600, 19200, 38400, 57600 (Defaults to 2400)
FBUS ID
Purpose: Sets the Fbus ID number used to identify the unit with Fbus communications.
Options: 01 to 99.
RESPONSE (Response time)
Purpose: This may be used to delay the instrument’s response to an fbus communication
command, typically for use with 2-wire RS485 connections to allow the master device
some additional time to disable its transmitter and prepare for the reply.
Options: 0 to 50 ms
FLASH (Flash Update Mode)
Purpose: Puts the unit into its Flash Updating mode. All 400 series transmitters can have their
program flash and/or Boot-Loader updated via the Furness Fbus Utility.
Please make sure you have your unit connected via a cable to a PC running the
Fbus Utility before selecting this option.
USER LIN (User Linearisation)
Purpose: This sub menu contains 5 sets of data that can be used for correcting non-linearity.
This feature gives users the ability to define 5 linearity correction points (stored as
%span), which can be used to modify the FCO432’s linearity. This can be used to
remove the non-linearity of an attached sensor such as a flow element.
POINT 1…5 (User Linearising Points)
Purpose: Sets each of the five linearity correction points. These are pressure points at which
an adjustment is required. The value is a percentage of the DP Span.
Options: 0.00 to 100.00.
%ADJ 1…5 (User Linearising Errors)
Purpose: Sets each of the five linearity correction errors. These are the errors present at each
of the defined points. Errors must be entered as a percentage of reading, where a