BEKA BA538C User manual

Issue: 12
25th March 2014
Label
information
Rate
display
Annunciators for
optional alarms
Rotating flow
indicator
Total
display
BA538C
Externally powered
pulse input
panel mounting
rate totaliser
issue 12

2
1. Description
2. Operation
2.1 Initialisation
2.2 Controls
2.3 Displays
3.System Design
3.1 Flow transmitter loops
3.2 Power supply
3.3 Pulse input
3.4 Remote reset
4. Installation
4.1 Location
4.2 Installation procedure
4.3 EMC
5. Programming and Calibration
5.1 Calibration structure
5.2 Accessing programme functions
5.3 Summary of programmable
functions.
5.4 Display update interval
5.5 Type of input
5.6 Position of the decimal points
5.7 Lower display
5.8 Rate scale factor
5.9 Timebase
5.10 Rate filter
5.11 Total scale factor
5.12 Clip-off
5.13 Local reset
5.14 Resetting grand total
5.15 Security code
6. Calibration Example
6.1 Calibration procedure
7. Maintenance
7.1 Fault finding during commissioning
7.2 Fault finding after commissioning
7.3 Servicing
7.4 Routine maintenance
7.5 Guarantee
7.6 Customer comments
8. Accessories
8.1 Scale card
8.2 Tag number
8.3 Alarms
8.3.1 Solid state output
8.3.2 Programming and
adjustment
8.3.3 Alarm enable
8.3.4 Type of alarm
8.3.5 Setpoint adjustment
8.3.6 Alarm function
8.3.7 Alarm output status
8.3.8 Hysteresis
8.3.9 Alarm delay
8.3.10 Alarm silence time
8.3.11 Access setpoint
8.3.12 Adjusting alarm setpoints
from display mode.
8.4 Display backlight
8.5 Pulse Output
8.6 4/20mA output
8.6.1 Programming & adjustment
9. Index
CONTENTS
The BA538C is CE marked to show compliance with the
European EMC Directive 2004/108/EC

3
1. DESCRIPTION
The BA538C is an externally powered pulse input
rate totaliser primarily intended for use with
flowmeters. The instrument simultaneously
displays the rate of flow and the total flow in
engineering units on two separate displays.
Housed in a robust 72 x 144 panel mounting DIN
enclosure, the BA538C has an IP65 front panel
and is supplied with a gasket to seal the joint
between the instrument and the panel.
2. OPERATION
Fig 1 shows a simplified block diagram of a
BA538C. The instrument accepts pulses from a
single source and after scaling displays the total
number of pulses received and their rate on
separate displays. When connected to a pulse
output flowmeter the BA538C will provide an
accurate display of total flow and the rate of flow.
The BA538C has two sets of input terminals for
connection to high or low level voltage pulses, a
switch contact, an open collector output or to a
two wire proximity detector. The instrument may
therefore be used with almost any pulse output
flowmeter. The total display may be reset to
zero by a remote switch contact or from the front
push-buttons.
Optional accessories enable the flow rate to be
transmitted to other equipment as an isolated
4/20mA analogue signal and the total flow to be
transmitted as a pulse signal. Optional alarms,
which may be programmed to function on the rate
or total displays, further extend the instrument’s
applications.
Fig 1 Simplified block diagram of BA538C
2.1 Initialisation
Each time power is applied to the instrument
initialisation is performed. After a short delay the
following display sequence occurs:
All segments of the display are activated for
about 2 seconds.
The product firmware number and the
version number are displayed for about 2
seconds.
Rate display and totaliser start to
function using calibration information
stored in the instrument's permanent
memory.
2.2 Controls
The BA538C is controlled and calibrated via four
front panel push-button switches. In the display
mode i.e. when the instrument is displaying rate
and total flow the switch functions are:
Description of Switch Functions
E+ Down While these buttons are pushed the
total display will show the least
significant eight digits of the grand
total, and the grand total annunciator
will be activated.
E+Up While these two buttons are pushed
the total display will show the most
significant eight digits of the grand total
and the grand total annunciator will be
activated.
Down Resets the total display to zero
+Up when these two push-buttons are
operated simultaneously for more than
two seconds.
Selectable function from programme
menu.
See section 5.12
Down While these buttons are pushed the
+P instrument will display the firmware
part number and version number.
Note: When optional alarms are fitted the push-
buttons may be programmed to have alternative
functions – see section 8.3

4
2.3 Displays
The BA538C has two digital displays and
associated annunciators, plus a flow indicator as
shown on page 1.
Rate Shows the flow rate on the
Display smaller six digit display.
Total Shows the total flow on the
display larger eight digit display. Set to
zero when local or remote reset
switch is operated.
Flow This disc in the lower left
indicator hand corner of the display 'rotates'
for two seconds each time an
input pulse is received. Therefore
when the pulse input frequency
exceeds 0.5Hz the disc appears
to rotate continuously.
Hold Activated when input
Annunciator frequency is below the clip-off
threshold.
Reset Activated when the instrument
Annunciator is being reset.
3. SYSTEM DESIGN
3.1 Flow transmitter loops
The BA538C may be connected to almost any
pulse output flowmeter and calibrated to display
rate of flow and total flow in the same or different
engineering units.
Fig 2 illustrates the basic circuit that is used for all
BA538C installations. For simplicity, connections
for the optional pulse output, 4/20mA output and
backlight are included in section 8 of this manual.
Fig 2 BA538C in flow application
When designing a system it is important to
remember that terminals 2, 4, 6 and 8 are
interconnected within the BA534D - see Fig 1.
3.2 Power supply
The BA538C may be powered from any dc supply
having an output voltage between 10 and 30V.
The instrument consumes about 12mA rising to
15mA when a proximity detector input is used.

5
3.3 Pulse input
As shown in Fig 2, the BA538C will count pulses
from a wide variety of transducers enabling it to
display the output from almost any flowmeter.
The instrument has one pulse input, but two sets
of input terminals enable it to accommodate
different types of transducers. Terminals 3 and 4
are for voltage pulse inputs and terminals 5 and 6
are for pulse sources that need powering i.e.
proximity detectors, switches and open collectors.
Note: Only one pair of input terminals may be
used at a time. i.e pulses can not be counted
from terminals 3 & 4 and from terminals 5 & 6 at
the same time.
The following table shows the switching
thresholds for the various transducers, plus the
maximum operating frequency and the input
terminal numbers. For reliable counting the input
signal must fall below the lower threshold and rise
above the upper threshold.
Switching
thresholds Freq max Input terminals
Switch 1001000100Hz 5 & 6
Proximity
detector 1.2mA 2.1mA 5 kHz 5 & 6
Open
collector 2k10k5kHz 5 & 6
Magnetic
pick-off 0mV 20mV peak 5kHz 3 & 4
Voltage
pulse 1.0V 3.0V 5kHz 3 & 4
3.4 Remote reset
The BA538C total display is reset to zero when
terminals 7 & 8 are connected together for more
than one second. Permanent interconnection of
these terminals will stop totalisation and may be
used as an inhibit function. There is no practical
limit on the distance that the reset switch may be
from the totaliser.
Alternatively, the BA538C may be programmed so
that the total display is reset to zero when the Up
and Down push-buttons are operated
simultaneously for more than two seconds. – see
5.12
4. INSTALLATION
4.1 Location
The BA538C is housed in a robust aluminium
enclosure with a polyester membrane front panel
surrounded by a Noryl bezel. The front of the
instrument provides IP65 protection and a gasket
seals the joint between the instrument enclosure
and the panel. The instrument may be installed in
any panel providing the environmental limits
shown in the specification are not exceeded.
Although the front panel of the instrument has
IP65 protection, the BA538C is not intended for
external mounting. Please refer to BEKA
associates if external mounting is required.
Fig 3 shows the overall dimensions of the BA538C
and the panel cut-out. To achieve an IP65 seal
between the instrument enclosure and the panel
the smaller cut-out must be used and the
instrument secured with four panel mounting clips.
The BA538C liquid crystal display has maximum
contrast when viewed from directly ahead and
slightly below the centre line of the instrument.
For reflective displays there is little degradation of
contrast when viewed from above the centre line,
but slight degradation may be noticeable when the
instrument is fitted with a backlight.
Fig 3 BA538C dimensions

6
4.2 Installation Procedure
a. Insert the BA538C into the instrument panel
cut-out from the front of the panel.
b. Fix panel mounting clips to opposite sides
of the instrument and tighten until the
instrument is secure as shown in Fig 4.
Four clips are required to achieve an IP65
seal between the instrument enclosure and
the panel.
c. Connect the panel wiring to the rear
terminal block(s) as shown in Fig 4 To
simplify installation, the terminals are
removable so that panel wiring can be
completed before the instrument is
installed.
Fig 4 Installation and terminal connections
4.3 EMC
The BA538C complies with the requirements of
the European EMC Directive 2004/108/EEC. For
specified immunity all wiring should be in
screened twisted pairs.
To prevent circulating currents, cable screens
should only be earthed at one point.

7
5. PROGRAMMING & CALIBRATION
The BA538C is programmed and calibrated via
four front panel push-buttons. All the programming
functions are contained in an easy to use menu
that is shown diagramatically in Fig 6. Each
function is summarised in section 5.3 and includes
references to more detailed information. Although
this simple menu driven system enables most
adjustments to be made without repeated
reference to this manual, it is recommended that
at least the summary of the programmable
functions in section 5.3 is read before attempting
programming or recalibration.
When the BA538C is fitted with alarms, a pulse
output or a 4/20mA output, the basic menu is
expanded to include the option(s). Section 8 of
this manual explains how to programme these
additional functions.
Note: While the instrument is being programmed
or calibrated, totalisation continues so that any
flow occurring during this time is recorded.
5.1 Calibration structure
Fig 5 shows the BA538C calibration structure.
The rate and total display calibration functions are
totally independent allowing the displays to have
different engineering units.
For the rate display the pulse input is divided by
SCALE-r to represent engineering units and
multiplied by the timebase t-bASE to calculate and
display the rate of flow per second, minute or
hour.
Similarly, to calculate the total flow in engineering
units the number of input pulses is divided by the
total scale factor SCALE-t. Total flow is
continuously added to the grand total.
The BA538C displays ‘real’ decimal points.
Moving the position of a decimal point in a scale
factor will therefore affect the instrument
calibration.
The BA538C updates its total flow calculation
twice per second. If the instrument is used for
batching applications, this resolution may define
the accuracy of the system.
Note: The total and rate displays may be updated
less frequently depending upon the display update
time selected.
Fig 5 Calibration structure
5.2 Accessing programming functions
Throughout this manual push-buttons are shown
in italics e.g. P or Up push-button, and legends
displayed by the instrument are shown within
inverted commas e.g. 'CAL' and ' ALr2'.
Access to the programme menu is obtained by
operating the Pand Epush-buttons
simultaneously. If the instrument is not protected
by a security code the first parameter 'UPdAtE' will
be displayed. If a security code other than the
default code 0000 has already been entered, the
instrument will display 'COdE'. Press Pto clear
this prompt and enter the security code for the
instrument using the Up or Down push-buttons to
adjust each digit, and the P push-button to move
control to the next digit. If the correct code has
been entered pressing Ewill cause the first
parameter 'UPdAtE' to be displayed. If an
incorrect code is entered, or a push-button is not
operated within ten seconds, the instrument will
automatically return to the display mode.
Apart from defining the position of the decimal
point in the rate display, all programme functions
and prompts are shown on the large eight digit
display.
Once within the main programme menu the
required parameter can be reached by scrolling
through the menu using the Up and Down push-
buttons as shown by the programme structure in
Fig 6.

8

9
All new BA538C rate totalisers are supplied
calibrated as requested at the time of ordering. If
calibration information is not supplied, the
instrument will be conditioned for an open
collector input, with SCALE-r and SCALE-t set to
1 and a timebase of seconds.
5.3 Summary of programmable functions
This section summarises all the programmable
functions. When read in conjunction with Fig 6 it
provides a quick aid for programming the
instrument. If more detail is required, each
section contains a reference to a full description of
the function.
SUMMARY
Display Description of function
‘UpdAtE’ Display update time
Allows the interval between
display updates to be selected.
See section 5.4
'InPut' Type of input
Enables one of five types of input
to be selected:
UOLtS Voltage pulse
COIL Magnetic pick-off
Pr.dEt NAMUR proximity
detector.
COntACt Switch contact
OP.COL Open collector
See section 5.5
'd.P.' Decimal points
Defines the position of the decimal
point in both the rate and total
displays and enables the rate and
total displays to be interchanged.
See section 5.6
‘dISPLAY.2’ Lower display
Turns the lower display, which
normally shows rate, on or off.
See section 5.7
Display Description of function
'SCALE-r' Rate Scale Factor
Defines the arithmetic relationship
between the pulse input frequency
and the rate display. May be
adjusted between 0.001 and
99999999.
When used with a flowmeter,
SCALE-r should be set to the
flowmeter K factor (pulses per unit of
measurement) if the display is
required in the same flow units as the
K factor.
See section 5.8
't-bASE' Timebase
Selectable multiplier to display flow
rate in units per second, per minute
or per hour.
Select: tb-1 for flow / second
tb-60 for flow / minute
tb-3600 for flow / hour
See section 5.9
'FILtEr' Rate filter
Adjustable digital filter to reduce
noise on the rate display. Two
parameters each adjustable between
0 and 9.
See section 5.10
'SCALE-t' Total Scale Factor
Defines the arithmetic relationship
between the number of input pulses
and the total display.
May be adjusted between 0.001 and
99999999.
When used with a flowmeter SCALE-
t should be set to the flowmeter K
factor (pulses per unit of
measurement).
See section 5.11
'CLIP-OFF' Clip off
To prevent the totalisation of very low
flow rates, clip-off enables the user to
select a flow rate below which
totalisation is inhibited.
See section 5.12

10
Display Description of function
'LOC.rSEt'Local reset of total display
When turned 'On' the total display
may be reset to zero from the display
mode by simultaneously operating
the Up and Down push-buttons for
more than two seconds.
See section 5.13
'CLr. Gtot'Clears grand total
This function resets the grand total to
zero when 'CLr YES' is selected, and
'SurE' is entered to confirm the
instruction.
Note: Once cleared, a grand total
can not be recovered.
See section 5.14
'COdE' Security code
Defines a four digit numeric code
which must be entered to gain
access to the programmable
functions. Default code 0000
disables the security function and
allows unrestricted access to all
programmable functions.
See section 5.15
5.4 Display update interval: ‘UpdAtE’
Six different intervals between display updates
varying between 0.5 and 5 seconds may be
selected. If either the rate or the total displays
are likely to change rapidly, a longer interval
between updates may simplify reading the
instrument display. The selected update interval
does not affect the update time of any other
instrument function such as the optional 4/20mA
output.
To define the update interval select ‘UpdAtE’ from
the main menu and press Pto reveal the current
time. Pressing the Up or Down button will scroll
through the six times. When the required interval
has been selected press Eto return to the main
menu.
5.5 Type of input: ‘InPut’
The BA538C may be programmed to accept pulse
inputs from a wide variety of sensors. To define
an input type select ‘InPut’ from the menu and
press Pwhich will reveal the current input type.
Pressing Up or Down will scroll through the five
options:
‘UOLts’ Voltage pulse input
Threshold 1V and 3V
5kHz max.
Input terminals 3 and 4
‘COIL’ Low voltage pulse
Threshold 20mV
peak 5kHz max.
Input terminals 3 and 4
‘Pr.dEt’ NAMUR proximity detector
Threshold 1.2 and 2.1mA
5kHz max.
Input terminals 5 and 6
‘COntACt’ Switch contact
Threshold 100 and 1000
100Hz max
Input terminals 5 and 6
‘OP.COL’ Open collector
Threshold 2kand 10k
5kHz max.
Input terminals 5 and 6
When the required type of input has been selected
press Eto return to the main menu.
Note: To count correctly, the input signal must fall
below the lower switching threshold and rise
above the higher switching threshold.
5.6 Position of the decimal points: ‘d.P.’
The rate display can have up to six digits and the
decimal point may be positioned between any of
them, or omitted. Similarly, the total display has
eight digits and the decimal point may be
positioned between any of them, or may be
omitted.
To adjust the position of either decimal point
select 'd.P.' from the main menu and press P. This
will activate both displays with one digit plus the
following decimal point of the total display
flashing. If only the least significant digit is
flashing, this indicates that the decimal point is
omitted.
The position of the decimal point can be moved by
pressing the Up or Down push-button. Operating
the P push-button will toggle control between the
two displays. When both decimal points have
been correctly positioned press Eto return to the
main menu.
If the application requires flow rate to be the
primary display i.e. shown on the large display,
the d.P. function enables the rate and total
displays to be interchanged. The rate display will
continue to have six digits but the total display will

11
be reduced from eight to six digits. The rate and
total annunciators will also be interchanged.
Pressing the Up and Down buttons simultaneously
will interchange the displays.
Note: Both decimal points must be repositioned
after the displays have been interchanged.
5.7 Lower display: ‘dISPLAY.2’
This function turns the lower display on or off.
When turned off, the BA538C will only have one
eight digit display which may be programmed to
show total flow or rate of flow.
5.8 Rate scale factor: ‘SCALE-r’
Together with the instrument timebase, this
function defines the arithmetic relationship
between the pulse input frequency and the rate
display. When used with a flowmeter SCALE-r
should be set to the K-factor of the flowmeter i.e.
the number of pulses the flowmeter produces for a
unit of flow. e.g. 45.6 pulses per litre. See
section 6 for a worked example.
SCALE-r is a dividing factor that may be adjusted
between 0.001 and 99999999.
To check or change the total scale factor select
'SCALE-r' from the main menu and press Pto
reveal the existing setting, one digit will be
flashing. The value of the flashing digit can be
changed by pressing the Up or Down buttons.
When this digit is correct pressing Pwill transfer
control to the next digit.
To position the decimal point in the rate scale
factor, move the flashing digit to the left hand side
of the required decimal point position and
simultaneously press the Up and Down buttons.
When the required rate scale factor has been
entered, press E to store the number and return to
the main menu.
5.9 Timebase: ‘t-bASE’
The timebase multiplies the rate display by 1, 60
or 3,600 depending upon whether the BA538C is
required to display rate per second, per minute or
per hour. See Fig 5.
To check or change the timebase, select 't-
bASE' from the main menu and press Pwhich will
reveal the current setting. Pressing the Up or
Down button will index through the three options:
tb-1 for flow / second
tb-60 for flow / minute
tb-3600 for flow / hour
Select the required multiplier and press Eto return
to the main menu.
5.10 Rate filter: ‘FILtEr’
This digital filter has two independent adjustable
parameters enabling the rate display frequency
response to be tailored for optimum performance.
The filter parameters are controlled by a two digit
number. The first digit defines the amount of
filtering applied to the display as shown below.
First digit Filter time constant
seconds
0X 0
1X 1.3
2X 4.3
3X 6.5
4X 8.7
5X 11.3
6X 15.7
7X 20.9
8X 25.2
9X 31.5
The second digit defines the deviation from the
displayed rate at which the filter will be overridden
and the rate display will move rapidly to the new
value.
Second
digit Magnitude of step change which will
produce a rapid
response
X0 Off
X1 1%
X2 2%
X3 4%
X4 8%
X5 12%
X6 16%
X7 24%
X8 32%
X9 64%
By careful adjustment of the two parameters a
stable display with an acceptable step input
response can be obtained for most applications.
During commissioning it is recommend that
initially the second digit is set to 0 (off) and the
first digit is adjusted to provide acceptable rate
display stability. The second digit should then be
increased until the selected step size is greater
than the noise on the display signal, at which
setting the rate display will again become stable.
These will be the optimum filter parameters for
acceptable rate display stability and a fast
response to a large rate signal change.

12
To check or change the filter select 'FILtEr' from
the main menu and press Pto reveal the current
settings. Pressing the Up or Down button will
change the flashing digit and Pwill transfer control
to the second digit. While making adjustments the
filtered rate display is shown on the lower display
so that stability can be assessed. When set as
required, press the Ebutton to enter the revised
parameters and return to the main menu.
5.11 Total scale factor: ‘SCALE-t’
This factor defines the arithmetic relationship
between the number of input pulses and the total
display. SCALE-t is a dividing factor that may be
adjusted between 0.001 and 99999999. See Fig
5.
When used with a flowmeter SCALE-t should be
set to the K-factor of the flowmeter i.e. the
number of pulses the flowmeter produces for a
unit of flow. If the BA538C total display is
required in units different from those in which the
flowmeter K factor is specified, a conversion factor
will be required.
e.g. If the flowmeter has a K factor of 45.6 pulses
per litre and the BA538C total display is required
in units of 1,000 gallons, then SCALE-t should be
set to number of pulses produced by the
flowmeter per 1,000 gallons:
45.6 x 4.54609 x 1000
207,301.7 pulses per 1000 gallons
(there are 4.54609 litres in a UK gallon)
To check or change the total scale factor select
'SCALE-t' from the main menu and press Pto
reveal the existing setting, one digit will be
flashing. The value of the flashing digit can be
changed by pressing the Up or Down buttons.
When this digit is correct pressing Pwill transfer
control to the next digit.
To position the decimal point in the scaling factor,
move the flashing digit to the left hand side of the
required decimal point position and
simultaneously press the Up and Down buttons.
When the required total scale factor has been
entered, press E to store the number and return to
the main menu.
5.12 Clip-off: ‘CLIP-OFF’
To prevent totalisation of very low flow rates that
over long periods may result in significant
totalisation errors, the BA538C may be
programmed to stop totalising when the flow rate
falls below an adjustable threshold.
To check or change the clip-off threshold select
'CLIP-OFF' from the main menu and press P
which will reveal the current setting. The
threshold is shown in the units already selected
for the flow rate display. One digit will be flashing.
The value of the flashing digit may be changed by
pressing the Up or Down buttons. When this digit
is correct pressing Pwill transfer control to the
next digit. When clip-off is set as required, press
the E button to enter the revised figure and return
to the main programme menu.
If the flow rate falls below the entered threshold,
the rate display will show zero flow, totalisation will
stop and the HOLD annunciator will be activated.
The flow indicator will rotate for 2 seconds each
time an input pulse is received i.e. at input
frequencies above 0.5Hz it will appear to rotate
continuously.
Note: When the rate scale factor SCALE-r, the
timebase t-bASE, or the position of the rate
display decimal point are changed, clip-off will
automatically be reset to zero. If required, a new
clip-off threshold may then be entered.
5.13 Local reset of total display:
‘LOC. rSEt’
When activated this function enables the operator
to reset the BA538C total display to zero in the
display mode by operating the Up and Down
push-buttons simultaneously for more than two
seconds. To check the status of the local reset
function select 'LOC.rSEt' from the menu and
press P which will reveal if the function is 'On' or
'OFF'. If necessary press the Up or Down button
to change the setting, followed by the E button to
return to the main menu.
The total display may also be reset to zero
remotely by connecting terminals 7 and 8
together. See section 3.4 of this manual.
5.14 Resetting grand total: ‘CLr. Gtot’
The grand total is a separate sixteen digit counter
which duplicates the total display but is not zeroed
when the total display is reset to zero. The grand
total may be viewed in the display mode in two
eight digit sections as described in section 2.2 of
this manual.

13
The grand total counter can only be reset to zero
from the 'CLr. Gtot' function in the main
programme menu. To zero the grand total
counter select 'CLr. Gtot' and press P which will
cause the instrument to display 'Clr. no' with 'no'
flashing. Continuously press the Up or Down
push-buttons until 'CLr. YES' is displayed and
then press Pwhich will result in a 'CLr 0000'
prompt with one digit flashing. Using the Up and
Down buttons and the P button to move to the
next digit, confirm the request by entering the
password 'SurE'. Note 'S' is entered as '5'.
Pressing E will then reset the grand total counter
to zero and return the instrument to the 'CLr. Gtot'
prompt in the main menu.
WARNING
After resetting the grand total
counter to zero the old grand total
can not be recovered.
5.15 Security code: ‘CodE’
The calibration and conditioning of the instrument
may be protected by a four digit security code
which must be entered before access to the
programme menu is granted. New instruments
are programmed with the default security code
0000 which allows unrestricted access to all
programming functions without entering a security
code.
To enter a new security code select 'COdE' from
the menu and press P which will cause the
instrument to display the current security code.
Each digit of the code can be changed using the
Up and Down push-buttons, and the Pbutton to
move to the next digit. When the required code
has been entered press E to return to the main
menu. The revised security code will be activated
when the indicator is returned to the display mode.
If the security code is lost, access to the
programmable functions can be obtained by
moving the internal security link to the override
position. The original security code can then be
viewed by selecting 'CodE' from the main menu
and pressing P.
To gain access to the security code link, remove
the instrument terminal block(s) by gently pulling.
Remove the five screws securing the rear panel
and lift off the panel to reveal the link – see Fig 7.
Fig 7 Location of security override link

14
6. CALIBRATION EXAMPLE
In this example a BA538C rate totaliser is
connected to a turbine flowmeter having a K-factor
of 1050.0 pulses per litre. The flowmeter has a
magnetic pick-off with an output greater than
20mV peak at 5 litres per minute and a usable
range of 5 to 60 litres per minute.
The BA538C is required to display rate of flow in
litres per hour with a resolution of one litre and
total flow in cubic metres with a resolution of 0.01
cubic metres. Totalisation is to stop when the
flow rate falls below 300 litres per hour. The
display is to be updated twice per second and
filtering is required. In this application the
operator needs to reset the total display to zero by
simultaneously pushing the Up and Down push-
buttons. To prevent tampering the instrument
programme menu is to be protected by security
code 1209
6.1 Calibration procedure
The BA538C rate totaliser may be calibrated on-
site without disconnection from the power supply
or from the flowmeter.
Step 1 Enter the programming mode
Put the BA538C in the programming
mode by simultaneously pressing P
and E. Assuming a security code has
not already been entered the
instrument will respond by displaying
'UPdAtE' which is the first function in
the main menu. See Fig 6.
Step 2 Select the interval between display
updates
With 'UPdAtE' displayed, press Pto
reveal the existing interval between
display updates. If this is not as
required, press the Up or Down button
until ‘0.5’ is displayed. (0.5 seconds i.e.
2 display updates per second). Enter
the revised time and return to the
'UPdAtE' prompt in the main menu by
pressing E.
Step 3 Select the type of input
Using the Up or Down button scroll
through the main menu until ‘InPut’ is
displayed, then press Pto reveal the
existing setting. Select ‘COIL’, the
input for a magnetic pick-off, using the
Up or Down button and return to the
'InPut' prompt in the main menu by
pressing E.
Note: The BA538C has two pairs of input
terminals. 3 & 4 for voltage inputs and
5 & 6 for switch contact, proximity
detector or open collector inputs.
Ensure that the magnetic pick-off,
which has a voltage output, is
connected to terminals 3 & 4.
Step 4 Position rate & total decimal points
Select ‘d.P.’ from the main menu and
press P. The rate and total displays
will be activated with one digit of the
total display flashing. Press the Up or
Down push-button until the third least
significant digit of the total display and
following decimal point are flashing.
This gives the required total display
resolution of 0.01
Press Pto move control to the rate
display. Using the Up or Down push-
button move the flashing digit to the
least significant position (right hand
side) which will result in no decimal
point being displayed.
Finally press Eto return to the 'd.P’.
prompt in the main menu.
Step 5 Enter the rate scaling factor
Select ‘SCALE-r’ from the main menu
and press Pto show the current figure.
The K factor of the flowmeter in this
example is 1050.0* pulses per litre
which should be entered as the rate
scaling factor.
Firstly to position the decimal point,
operate the Ppush-button to move the
flashing digit to the second least
significant position. Pressing the Up
and Down buttons simultaneously will
then position the decimal point in front
of the least significant digit.
Using the Up and Down buttons to
adjust each digit in turn and the P
button to transfer control between
digits, enter 1050.0 Finally return to
the 'SCALE-r' prompt in the main menu
by pressing E.
* May also be entered as 1050

15
Step 6 Enter the rate timebase
Select ‘t-bASE’ from the main menu
and press Pto show the current
setting. In this example the rate
display is required in litres per hour.
Using the Up or Down button scroll
through the three options and select
‘tb-3600’ which will multiply the rate
display by 3600. Return to the ‘t-bASE’
prompt in the main menu by pressing
E.
Step 7 Adjust the rate filter
The rate display filter parameters
should be adjusted experimentally after
installation to provide a stable rate
display with an acceptable step
response.
During commissioning it is recommend
that initially the second digit of the rate
parameters is set to 0 (step response
off) and the first digit (amount of
filtering) is adjusted to provide
acceptable rate display stability. The
second digit should them be increased
until acceptable rate display stability is
once again achieved.
To adjust the filter parameters select
‘FILtEr’ from the main menu and press
Pto reveal the current setting. The
first digit will be flashing and may be
adjusted using the Up or Down button.
The Pbutton will transfer control to the
second digit. When both are set as
required, return to the ‘FILtEr’ prompt
in the main menu by pressing E.
Step 8 Enter the total scaling factor
The K factor of the flowmeter in this
example is 1050.0 pulses per litre and
the total display is required in cubic
metres.
There are 1000 litres in a cubic metre
so the BA538C is required to display 1
cubic metre for every 1,050 x 1,000
pulses received. ‘SCALE-t’ should
therefore be set to 1,050,000
Select ‘SCALE-t’ from the main menu
and press Pwhich will reveal the
current setting with one digit flashing.
To position the decimal point, operate
the Ppush-button to move the flashing
digit to the least significant position.
Pressing the Up and Down buttons
simultaneously will then remove the
decimal point.
Using the Up and Down buttons to
adjust each digit in turn and the P
button to transfer control between
digits, enter 1050000 Finally return to
the 'SCALE-t' prompt in the main menu
by pressing E.
Step 9 Define clip-off
In this example totalisation is to be
inhibited at flow rates below 300 litres
per hour.
Select ‘CLIP-OFF’ from the main menu
and press Pwhich will reveal the clip-
off threshold in litres per hour i.e. the
same units already selected for the
rate display. The most significant digit
of the display will be flashing,
indicating that this digit may be
adjusted. Pressing P five times will
move the flashing digit to the third
lease significant digit.
Using the Up and Down buttons set
the third least significant digit to 3 i.e.
a clip-off threshold of 300. Finally
return to the 'CLIP-OFF' prompt in the
main menu by pressing E.
Step 10 Turn local reset on
In this example the operator needs to
reset the total display to zero by
pressing the Up and Down buttons
simultaneously. To activate the local
reset function select ‘LOC.rSEt’ from
the main menu and press Pto display
the current setting. Pressing the Up or
Down button will toggle the display
between ‘On’ and ‘OFF’. Select ‘On’
and press Eto return to the ‘LOCrSEt’
prompt in the main menu.

16
Step 11 Reset the grand total to zero
Before completing commissioning the
grand total counter should be reset to
zero. Select 'CLr. Gtot' from the main
menu and press P which will cause the
instrument to display 'Clr. no'. Toggle
this to 'CLr. YES' using the Up or
Down push-buttons and press Pwhich
will result in a '0000' prompt. Using the
Up, and Down buttons and the P
button to move to the next digit,
confirm the request by entering the
password 'SurE'. Note: S is entered as
5. Pressing E will then reset the
grand total counter to zero and return
the instrument to the 'CLr. Gtot' prompt
in the main menu.
Step 12 Define the security code
Defining a security code prevents
unauthorised access to the programme
functions. Select 'COdE' from the
main menu and press Pwhich will
reveal the existing security code.
Using the Up and Down buttons enter
the new code 1209 digit by digit. The
Pbutton will transfer control between
digits. When the new code has been
entered, press Eto return to the main
programme menu.
Step 13 Return to the display mode
Following completion of programming
and calibration, return the BA538C to
the operating mode by pressing E. All
the programming functions will now be
stored in permanent memory and will
be protected from accidental or
unauthorised adjustment by the
security code.

17
7. MAINTENANCE
7.1 Fault finding during commissioning
If a BA538C fails to function during commissioning
the following procedure should be followed:
Symptom Cause Check:
No display Incorrect
wiring
Note:
Terminals 2, 4,
6 & 8 are
interconnected
within the
BA538C
That there is
between 10 and
30V on terminals
1 & 2 with terminal
1 positive.
Flow indicator
not rotating No input pulses,
incorrect input
terminals
used, or
incorrect type
of input
selected
That BA538C has
been calibrated for
the correct input.
That input signal
polarity is correct.
Flow indicator
rotating but
incorrect rate
display
Incorrect
calibration
Input below
clip-off
threshold
That rate scale
factor and
timebase are
correctly
programmed.
That clip-off
threshold is set
correctly.
Unstable rate
display Noisy pulse input signal Source of electrical noise and try to
eliminate or
increase rate filter.
Correct rate
display but
incorrect total
display
Incorrect
calibration
Remote reset
switch
contacts
closed
That total scale
factor is correctly
programmed.
That ‘RESET’
annunciator is not
activated. If it is,
check reset wiring
and switch.
Unable to
enter
programme
mode
Incorrect
security code That the correct security code is
being used, or fit
security link in
override position.
See Fig 7
Clip-off does
not function
and 4/20mA
output is
constantly
3.5mA
Clip-off &
4/20mA have
been
automatically
reset to zero
following
change of rate
display
calibration
Re-enter required
clip-off and
4/20mA output
calibration.
Alarms do not
function Alarms have been disabled
following
calibration
change
Re-enable both
alarms.
7.2 Fault finding after commissioning
ENSURE PLANT SAFETY BEFORE
STARTING MAINTENANCE
If a BA538C fails after it has been functioning
correctly, the following table may help to identify
the cause of the failure.
Symptom Cause Check:
No display No power
supply. That there is between 10 and
30Von terminals 1
& 2.
Flow indicator
not rotating No input pulses Output from flowmeter
Wiring between
flowmeter and
BA538C
Flow indicator
rotating, but
rate display
indicates zero
and there is
no totalsiation
Input below
clip-off
threshold
Clip-off threshold
and if necessary
adjust.
Unstable rate
display Noisy pulse input signal Source of electrical noise and try to
eliminate, or
Increase rate filter.
If this procedure does not reveal the cause of the
fault, it is recommended that the instrument is
replaced.
7.3 Servicing
We recommend that faulty BA538C rate totalisers
are returned to BEKA associates or to our local
agent for repair.
7.4 Routine maintenance
The mechanical and electrical condition of the
instrument should be regularly checked. Initially
annual inspections are recommended, but the
inspection frequency should be adjusted to suit
environmental conditions.
7.5 Guarantee
Instruments which fail within the guarantee period
should be returned to BEKA associates or our
local agent. It is helpful if a brief description of the
fault symptoms is provided.
7.6 Customer comments
BEKA associates is always pleased to receive
comments from customers about our products and
services. All communications are acknowledged
and whenever possible, suggestions are
implemented.

18
8. ACCESSORIES
8.1 Scale card
The BA538C has a window on the right hand side
of the display to hold a card showing the units of
measurement e.g. Litres, Gallons, m3.
Instruments can be supplied with a printed scale
card showing any units specified at the time of
ordering. If a printed card is not requested, a
blank card will be supplied.
Scale cards can easily be marked on-site as
follows:
a. Remove the rear terminal block(s) and the
rear panel as shown in Fig 7.
b. Carefully pull the rate totaliser assembly
from the enclosure.
c. Gently pull and then slide the blank scale
card towards the display window until the
card is free. Mark the card with the
required legend and replace in the slot.
d. Reassemble the instrument.
8.2 Tag number
The BA538C can be supplied with a thermally
printed tag number on the rear panel. This tag
number is not visible from the front of the
instrument after installation.
8.3 Alarms
The BA538C can be supplied with two solid state
single pole outputs which may be independently
programmed as high or low, rate or total alarms
with normally open or normally closed outputs.
WARNING
These alarm outputs should not be used
for critical safety applications such as a
shut down system.
When the BA538C power supply is turned off or
disconnected, both BA538C alarm outputs will
open irrespective of whether normally open or
normally closed outputs have been selected.
When designing a system an open output should
therefore be the alarm condition.
Alarm annunciators on the instrument display
indicate the status of both alarms. If an alarm
delay or silence time has been selected the
annunciator will flash during the delay or silence
period.
Programmable functions for each alarm include
adjustable setpoint, alarm delay time and alarm
silence time. Hysteresis may be applied to rate
alarms.
The BA538C total display is up-dated and
compared with the programmed alarm setpoint
twice per second, irrespective of the display
update time selected. This may result in the total
alarm being delayed for up to half a second after
the total has exceeded the setpoint.
8.3.1 Solid state output
Each alarm has a galvanically isolated single pole
solid state switch output as shown in Fig 8. The
outputs are polarised and current will only flow in
one direction. Terminals A1 and A3 should be
connected to the positive side of the supply.
Ron = 5+ 0.6V
Roff = greater than 180k
Note: Because of the series protection diode
some test meters may not detect a closed
alarm output
Fig 8 Equivalent circuit of each alarm output
Fig 9 Typical alarm application

19
8.3.2 Programming and adjustment
When a BA538C is supplied with alarms the main
programme menu is extended as shown in Fig 10.
The two alarm functions appear between the
'LOC-rSEt' and the 'CLr.Gtot' functions. Each
alarm may be programmed as a rate or as a total
alarm.
For simplicity Fig 10 only shows the
programmable functions on the rate option of
alarm AL1. Alarm 2 and the total options are
identical except that the total alarms do not have
hysteresis.
The following table summarises each of the alarm
programme functions and includes a cross
reference to more detailed information. Again
only the functions on alarm AL1 are listed.
Summary of programmable alarm functions
Display Description of function
'EnbL' Alarm enable
Enables or disables the alarm function
without changing the alarm
parameters.
See section 8.3.3
'tYPE' Type of alarm
Defines whether the alarm operates on
the rate or total display.
See section 8.3.4
'SPr1' Alarm setpoint 1
or Adjusts the alarm setpoint. The
‘SPt1’ alarm is activated when the rate or
total display equals the setpoint.
Note: ‘SPr1’ is displayed for a rate
alarm and ‘SPt1’ for a total alarm.
See section 8.3.5
'HI.LO' Alarm function
Defines whether the alarm has a high
or low function
See section 8.3.6
'no.nc' Normally open or normally closed
output
Determines whether the single pole
alarm output is open or closed in the
non-alarm condition.
See section 8.3.7
'HStr' Hysteresis
Adjusts the alarm hysteresis. Only
available on rate alarms.
See section 8.3.8
'dELA' Alarm delay time
Adjusts the delay between the display
equalling the setpoint and the alarm
output being activated.
See section 8.3.9
'SIL' Alarm silence time
Defines the time that the alarm output
remains in the non-alarm condition
following acceptance of an alarm.
See section 8.3.10
'AcSP' Access setpoint
Sub-menu that enables direct access
to the alarm setpoints from the display
mode and defines a separate security
code.
See section 8.3.11

20
8.3.3 Alarm enable: ‘EnbL’
This function allows the alarm to be enabled or
disabled without altering any of the alarm
parameters. To check or change the function
select 'EnbL' from the alarm menu and press P
which will reveal the current setting. The function
can be changed by pressing the Up or Down
button followed by the Ebutton to return to the
alarm menu.
Note: The alarms will be automatically disabled
after the rate or total displays have been
recalibrated, or the alarm type has been changed.
Both alarms must therefore be enabled after
calibration changes.
8.3.4 Type of alarm: ‘tYPE’
Alarm 1 and Alarm 2 may both be rate or total
alarms, or one may be conditioned for rate and
the other for total.
To check or change the type of alarm, select
'tYPE' from the alarm menu and press Pwhich will
reveal the current setting. The function can be
changed by pressing the Up or Down button
followed by the Ebutton to return to the alarm
menu.
Note: When ‘tYPE’ is changed, the alarm
parameters are automatically set to the default
values and the alarm disabled. It must therefore
be reprogrammed before use.
Fig 10 Alarm menu structure