BEKA BA377E User manual

Issue: 6
4th May 2021
BA377E
Single input
Intrinsically safe
Ti er or Clock
Issue 6

2
1. DESCRIPTION
2. INTRINSIC SAFETY CERTIFICATION
2.1 ATEX gas certification
2.2 Zones, gas groups and T rating
2.3 Special conditions for safe use
2.4 Po er supply
2.5 Input terminals
2.5.1 Sensors that do not require
energising.
2.5.2 Sensors that require energising
2.6 Remote reset terminals
2.7 Control outputs - optional
2.8 Certification label information
3. SYSTEM DESIGN FOR HAZARDOUS AREAS
3.1 Use ith Zener barriers
3.1.1 Po er supply
3.1.2 Sensor inputs
3.1.3 S itch contact input
3.1.4 Open collector input
3.1.5 2- ire proximity detector input
3.1.6 Magnetic pick-off input
3.1.7 Voltage input
3.1.8 Remote reset
3.1.9 Control outputs - optional
3.2 Use ith Galvanic Isolators
3.2.1 Po er supply
3.2.2 Sensor inputs
3.2.3 S itch contact input
3.2.4 Open collector input
3.2.5 2- ire proximity detector input
3.2.6 Magnetic pick-off input
3.2.7 Voltage input
3.2.8 Remote reset
3.2.9 Control outputs - optional
4. INSTALLATION
4.1 Location
4.2 EMC
4.3 Installation Procedure
4.4 Scale card
5. ACCESSORIES
5.1 Display backlight
5.2 Control outputs
5.3 Scale card
5.4 Tag information
5.5 Rear cover sealing kit
6. OPERATION AS A TIMER
6.1 Initialisation
6.2 Controls hen configured as a Timer
6.3 Displays hen configured as a Timer
6.4 Timer structure
6.5 Configuration as a Timer
6.5.1 Accessing configuration functions
6.5.2 Summary of Timer configuration
functions.
6.5.3 Instrument function: FunCtion
6.5.4 Input: inPut
6.5.5 Input type: inP . tYPE
6.5.6 debounce: debounce
6.5.7 Lo er display: di5P-2
6.5.8 Starting & stopping the Timer:
5tAr5toP
6.5.9 Units of display: unit5
6.5.10 Set time: 5Et t
6.5.11 Repeat timing cycle: CYCLE5
6.5.12 Cycle function enable: EnbL
6.5.13 Cycle count: cycl cnt
6.5.14 Restart delay: r5t dela
6.5.15 Adjusting the set time 5Et t and
restart delay r5t dela from the
display mode: AC5Et t
6.5.16 Direction of count: uP or dn
6.5.17 Po er fail: p fail
6.5.18 Local reset: LoC rEt
6.5.19 Local total reset: rE5Et . enbl
6.5.20 Local grand total reset: clr Gtot
6.5.21 Control output 1 (Optional): oP1
6.5.22 Control output 1 enable: EnbL
6.5.23 Control output on at: oP1 on
6.5.24 Control output off at: oP1 oFF
6.5.25 Output on delay time: oP1 dELA
6.5.26 Control output 2 (Optional): oP2
6.5.27 Reset grand total from ithin the
configuration menu: Clr Gtot
6.5.28 Security code: CodE
6.5.29 Reset configuration to Timer
factory defaults: r5Et dEF
7. TIMER APPLICATION EXAMPLES
7.1 Measuring the time that a contact is closed
7.2 Controlling an IS solenoid valve
CONTENTS
The BA377E is CE marked to sho compliance ith the European Explosive Atmospheres Directive
2014/34/EU and the European EMC Directive 2014/30/EU

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8 MAINTENANCE when configured as a Ti er
8.1 Fault finding during commissioning
8.2 Fault finding after commissioning
8.3 Servicing
8.4 Routine maintenance
8.5 Guarantee
8.6 Customer comments
9. OPERATION AS A CLOCK
9.1 Initialisation and loss of po er
9.2 Controls hen configured as a clock
9.3 Displays hen configured as a clock
9.4 Configration as a clock
9.4.1 Accessing configuration functions
9.4.2 Summary of Clock configuration
functions.
9.4.3 Instrument function: FunCtion
9.4.4 Display format: di5PLAY
9.4.5 Set Clock display time: 5et
9.4.6 Enter synchronising time: 5YnC t
9.4.7 Control output 1 (Optional): oP1
9.4.8 Enable Control output 1: EnbL
9.4.9 On and off times:
oP 1 : on 1; oP 1 : off 1
oP 1 : on 2; oP 1 : off 2
9.4.10 Control output 2 (Optional): oP2
9.4.11 Enable control output 2: EnbL
9.4.12 On and off times:
oP2 : on 1; oP2 : off 1
oP2 : on 2; oP2 : off 2
9.4.13 Access on & off times from display
mode: AC5P
9.4.14 Security code: CodE
9.4.15 Reset configuration to Clock
factory defaults: r5Et dEF
10. CLOCK CONFIGURATION EXAMPLE
10.1 Configuration procedure
11. MAINTENANCE when configured as a Clock
11.1 Fault finding during commissioning
11.2 Fault finding after commissioning
11.3 Servicing
11.4 Routine maintenance
11.5 Guarantee
11.6 Customer comments
Appendix 1
IECEx gas certification
Appendix 2
ETL and cETL certification

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1. DESCRIPTION
The BA377E is an intrinsically safe, panel mounting
instrument ith a single input that can be configured
as a Timer or as a Clock. As a Timer the BA377E is
able to measure and display the elapsed time
bet een external events, or control external events
via t o optional factory fitted control outputs.
When configured as a Clock, the instrument can
display time in a variety of formats and the t o
optional control outputs may be configured to s itch
loads on and off at pre-set times.
This instruction manual is divided into sections.
Co on features
2. Intrinsic safety certification
3. System design for hazardous areas
4. Installations
5. Accessories
Ti er
6. Operation as a timer
7. Configuration example
8. Maintenance
Clock
9. Operation as a clock
10. Configuration example
11. Maintenance
The common features sections of this instruction
manual describe ATEX certification for use in gas
atmospheres.
For international applications the BA377E has IECEx
gas certification hich is described in Appendix 1.
For applications in the USA and Canada the BA377E
has ETL and cETL certification hich is described in
Appendix 2.
This instruction manual supplements the abbreviated
instruction sheet supplied ith each instrument.
2. INTRINSIC SAFETY CERTIFICATION
The BA377E has IECEx and ATEX gas certification.
This section of the instruction manual describes
ATEX gas certification. IECEx and other approvals
are each described in separate appendixes to this
manual. The intrinsic safety of the instrument is
unaffected by hether it is configured as a Timer or
as a Clock.
2.1 ATEX gas certification
Notified Body Intertek Testing and Certification Ltd
have issued the BA377E ith an EC-Type
Examination Certificate number ITS16ATEX28408X.
This confirms compliance ith harmonised European
standards and this certificate has been used to
confirm compliance ith the European ATEX
Directive for Group II, Category 1G equipment. The
instrument carries the community mark and subject
to local codes of practice may be installed in any of
the European Economic Area (EEA) member
countries. ATEX certificates are also acceptable for
installations in other countries such as S itzerland.
This instruction manual describes ATEX installations
in explosive gas atmospheres conforming ith
EN60079-14 Electrical Installations design, selection
and erection. When designing systems for
installation outside of the UK the local Code of
Practice should be consulted.
2.2 Zones, gas groups and T rating
The BA377E has been certified Ex ia IIC T5 Ga
-40°C ≤ Ta ≤ 70°C. When connected to a suitable
system it may be installed in:
Zone 0 explosive gas air mixture
continuously present.
Zone 1 explosive gas air mixture likely
to occur in normal operation.
Zone 2 explosive gas air mixture not
likely to occur, and if it does
ill only exist for a short time
Be used ith gases in groups:
GroupA propane
GroupB ethylene
GroupC hydrogen
In gases that may be used ith equipment having a
temperature classification of:
T1 450°C
T2 300°C
T3 200°C
T4 135°C
T5 100°C
At ambient temperatures bet een -40 and +70°C.

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The specified operating temperature for the BA377E
is -40 to +70°C. At temperatures belo -20°C the
instrument ill continue to function, but the display
digits ill change more slo ly and the contrast ill
be reduced.
This allo s the BA377E to be installed in all gas
Zones and to be used ith most common industrial
gases except carbon disulphide and ethyl nitrite
hich have an ignition temperature of 95°C.
2.3 Special conditions for safe use
The ATEX certificate has an 'X' suffix indicating that
special conditions apply to prevent an electrostatic
charge developing on the outside of the instrument
enclosure.
WARNING
To avoid an electrostatic charge being
generated instru ent enclosure should
only be cleaned with a da p cloth.
2.4 Power supply
When installed in a hazardous area the BA377E
must be po ered via a certified Zener barrier or
galvanic isolator from a dc supply located in the safe
area, or from certified associated apparatus ith an
intrinsically safe output.
The input safety parameters of the BA377E po er
supply terminals 1 and 2 are:
Ui = 28V dc
Ii = 200mA dc
Pi = 0.84W
Any certified Zener barrier or galvanic isolator ith
output safety parameters equal to or less than these
limits may be used to po er the BA377E.
The maximum equivalent capacitance and
inductance bet een terminals 1 and 2 is:
Ci = 2nF
Li = 4µH
To determine the maximum permissible po er
supply cable parameters the above figures, hich
are small and may be ignored for many applications,
should be subtracted from the maximum permitted
parameters, Co and Lo, specified for the Zener
barrier or galvanic isolator po ering the BA377E.
2.5 Input ter inals
When configured as a Timer the BA377E is
controlled via a single input that may be configured
for use ith different types of sensor. The input is a
separate intrinsically safe circuit, although the
negative side is internally connected to the negative
side of the po er supply and the reset terminal RS2.
See Fig 9.
Some types of sensor that may be connected to the
BA377E input, such as a s itch contact or a 2- ire
proximity detector, require energising to determine
their state. For sensors requiring energising fitting
an external link bet een terminals 3 & 4 connects an
internal 7V, 6mA supply to the input. Energising is
not required hen the BA377E input is connected to
a voltage source.
Fitting an energising link changes the output safety
parameters of the BA377E input as sho n in the
follo ing table hich also sho s the types of sensor
requiring energising (link fitting).
Output safety
para eters of
input ter inals 5 & 6.
Type of input Link* Uo Io Po
S itch contact Yes 10.5V 9.2mA 24mW
Proximity detector Yes 10.5V 9.2mA 24mW
Open collector Yes 10.5V 9.2mA 24mW
Magnetic pick-off No 1.1V 0.5mA 0.2mW
Voltage input (lo ) No 1.1V 0.5mA 0.2mW
Voltage input (high) No 1.1V 0.5mA 0.2mW
*Link terminals 3 and 4
2.5.1 Sensors that do not require energising
Sensors ith a voltage output do not require
energising, therefore terminals 3 & 4 should not be
linked. When not energised i.e. ithout a link the
BA377E input complies ith the requirements for
simple apparatus. For intrinsic safety purposes,
sources of energy ith output parameters less than
1.5V; 100mA and 25mW are considered to be simple
apparatus (Clause 5.7 of EN60079-11), hich allo s
them not to be considered or documented hen
assessing the safety of an intrinsically safe system,
thus simplifying loop assessment.
This allo s almost any voltage output sensor to be
directly connected to the BA377E input in a
hazardous area providing that:
a. The sensor is a certified intrinsically safe device
having output parameters equal to or less than:
Uo ≤ 28V dc
Io ≤ 200mA dc
Po ≤ 0.84W
or complies ith requirements for
simple apparatus.
b. The sensor and associated iring can
ithstand a 500V rms insulation test to earth.
c. The sensor is located in the same hazardous
area as the BA377E.

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The BA377E EC-Type Examination Certificate
specifies that the equivalent capacitance and
inductance of the BA377E sensor input is:
Ci = 2nF
Li = 4µH
To determine the maximum permissible cable
parameters these figures should be subtracted from
the maximum permitted output parameters Lo and
Co specified by the certificate for the sensor
connected to the BA377E input terminals. The
BA377E input parameters are small and therefore
unlikely to make a significant difference to the
allo able cable parameters.
2.5.2 Sensors that require energising
S itch contacts, proximity detectors and open
collector sensors require energising hich is
achieved by linking t o BA377E terminals together
as described in section 2.5. When energised, the
output parameters of the BA377E input are:
Uo = 10.5V dc
Io = 9.2mA dc
Po = 24mW
These parameters do not comply ith the
requirements for simple apparatus and should be
considered hen assessing the safety of the sensor
connected to a BA377E input.
Any certified intrinsically safe sensor may be
connected to the BA377E energised input providing
that the sensor's input safety parameters are equal
to, or greater than, the output safety parameters of
the BA377E input sho n above. This is not
restrictive and most intrinsically safe sensors ill
comply. A sensor complying ith the requirements
for simple apparatus, such as a mechanically
operated s itch contact, may also be connected.
This allo s most mechanically operated s itches,
open collector transistors and certified intrinsically
safe NAMUR proximity detectors to be directly
connected to the BA377E energised input. The
sensor and iring should be able to ithstand a
500V rms insulation test to earth and the sensor
should be located in the same hazardous area as the
BA377E.
The maximum capacitance and inductance that may
be safely connected to the energised input (link
connected) is:
Co = 2.4µF
Lo = 200mH
Again this is not restrictive as the combined
capacitance and inductance of most sensors and
connecting cable ill be less than this.
2.6 Re ote reset ter inals
Connecting the external reset terminals RS1 and
RS2 together ill reset the BA377E hen configured
as a Timer and synchronise the displayed time hen
configured as a Clock. The t o reset terminals have
the follo ing input and output safety parameters:
Uo = 3.8V dc
Io = 1.6mA dc
Po = 2.0mW
Ui = 28V dc
Ii = 200mA dc
Pi = 0.84W
The equivalent capacitance and inductance bet een
them is:
Ci = 0nF
Li = 0µH
The maximum cable capacitance and inductance
that may be safely connected bet een the reset
terminals RS1 and RS2 is:
Co = 40µF
Lo = 1H
The reset terminals may be directly connected to any
mechanically operated s itch located ithin the
same hazardous area as the BA377E. The s itch
and associated iring should be able to ithstand a
500V insulation test to earth.
If the reset s itch is required in the safe area a
Zener barrier or intrinsically safe relay is required to
transfer the contact closure into the hazardous area.
Almost any intrinsically safe relay ith certification
permitting the contacts to be connected to equipment
in the hazardous area may be used. A positive diode
return Zener barrier may also be used as sho n in
Fig 1.
When used as a Timer the BA377E may also be
reset from the display mode by operating the & and
push buttons simultaneously for more than t o
seconds. See 6.5.19

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2.7 Control outputs - optional
Each of the t o factory fitted optional control outputs
is a separate galvanically isolated intrinsically safe
circuit ith output safety parameters complying ith
the requirements for simple apparatus. This allo s
the control output terminals A1 & A2 and A3 & A4 to
be connected to almost any intrinsically safe circuit
protected by a Zener barrier or galvanic isolator
providing the output safety parameters of the circuit
do not exceed:
Uo ≤ 28V dc
Io ≤ 200mA dc
Po ≤ 0.84W
The maximum equivalent capacitance and
inductance bet een each set of control output
terminals is:
Ci = 24nF
Li = 8µH
To determine the maximum permissible cable
capacitance Ci should be subtracted from the
maximum permitted external capacitance Co
specified by the certificate for the intrinsically safe
interface po ering the circuit being s itched by the
control output. See figs 4 & 5.
2.8 Certification label infor ation
The BA377E product certification label is fitted in a
recess on the top outer surface of the enclosure. It
sho s the ATEX and IECEx certification information
plus BEKA associates name and location and the
instrument serial number. Certification information
from other authorities may also be included.
BA377E Certification information label

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3. SYSTEM DESIGN FOR HAZARDOUS
AREAS
3.1 Use with Zener barriers
Zener barriers are the least expensive intrinsically
safe interface bet een a safe and hazardous area.
Ho ever, they require a high integrity earth
connection that may be expensive to install and they
do not provide isolation. When a high integrity earth
connection is not already available, it may be less
expensive and complicated to use galvanic isolators
for the installation of a single BA377E.
Terminals 2, 6 and RS2 of the BA377E are internally
connected together as sho n in Fig 9. If any of
these terminals are earthed, as sho n in Figs 1 & 2,
the other common terminals should only be
connected to the same earth, i.e. the barrier busbar,
or to circuits that have at least 500V insulation to
earth.
Any Zener barrier certified for the gas group and
Zone in hich the BA377E is installed may be used,
providing the output parameters do not exceed the
input parameters of the BA377E terminals to hich it
is connected. Only one polarity of Zener barrier i.e.
positive or negative may be used in each system.
Fig 1 illustrates the basic circuit that is used for all
BA377E Timer installations protected by Zener
barriers. BA377E Clock installations are the same,
except that the input terminals 5 & 6 are not used.
For simplicity the optional control outputs are
described separately in section 3.1.9 of this manual.
Fig 1 BA377E Timer used ith Zener barriers
Alternatively the sensor may be located in the safe
area. Fig 2 sho s ho an additional Zener barrier is
used to transfer signals to the Timer in the
hazardous area.
When more than one Zener barrier is used in a
system all must have the same polarity. i.e. all
positive or all negative barriers. When designing a
Timer system it is important to remember that
terminals 2, 6 and RS2 of the BA377E are connected
together ithin the instrument. Similarly, terminals 2
and RS2 are internally connected together hen the
BA377E is configured as Clock. See Fig 18.
Fig 2 BA377E Timer used ith Zener barriers ith
input sensor in the safe area.
3.1.1 Power supply
The BA377E requires a minimum of 10V bet een
terminal 1 & 2 and consumes:
10mA ithout optional backlight
plus 22mA ith optional backlight
plus 6mA hen terminals 3 & 4 are linked
Any Zener barrier certified for the gas group and
Zone in hich the BA377E is installed may be used
to po er the instrument, providing the output safety
parameters of the barrier are equal to or less than
the input safety parameters of terminals 1 & 2.
Although this allo s a ide variety of barriers to be
used, a positive polarity 28V; 93mA; 300 Zener
barrier, hich has an end-to-end resistance of about
340, is an industry standard device hich is
frequently used. With this barrier the supply voltage
in the safe area must be bet een the minimum value
sho n belo and the maximum orking voltage of
the Zener barrier hich, depending upon
manufacturer, ill be approximately 26V.
13.5V min ithout optional backlight
20.9V min ith optional backlight
plus 2.1V hen terminals 3 & 4 are linked

9
3.1.2 Sensor input
When configured as a Timer the sensor input may be
connected to a ide variety of hazardous area
devices as sho n in Fig 1, or to safe area sensor as
sho n in Fig 2. The input must be maintained not
momentary. The BA377E input is not used hen the
instrument is configured as a Clock.
No Zener barrier is required in series ith the input if
the intrinsically safe sensor is located ithin the
same hazardous area as the BA377E. The follo ing
table sho s the instrument's input s itching
thresholds hen configured to operate ith various
sensors. For reliable operation the BA377E input
must fall belo the lo er threshold and rise above
the upper threshold.
Sensor Switching thresholds
Lower Upper
Low voltage range 1.0V 3.0V
High voltage range 3.0V 10.0V
Proxi ity detector 1.2mA 2.1mA
Switch 1001000
Open collector 2k10k
S itch contacts, proximity detectors and open
collector sensors require energising hich is
achieved by linking terminals 3 and 4 together as
described in section 2.5.
3.1.3 Switch contact input
Any mechanically activated s itch contact may be
directly connected to input terminals 5 & 6 providing
the s itch is located in the same hazardous area as
the BA377E, and the s itch and associated iring
can ithstand a 500V rms insulation test to earth.
Most industrial push buttons and magnetically
activated reed relays comply ith these
requirements. The BA377E contains a configurable
debounce circuit to prevent false triggering of the
instrument. Three levels of debounce protection are
available. See section 6.5.6.
3.1.4 Open collector input
Any sensor ith an open collector output located in
the same hazardous area as the BA377E, such as a
mechanically activated opto-isolator may be directly
connected to input terminals 5 & 6. The sensor and
the associated iring must be able to ithstand a
500V rms insulation test to earth. The BA377E
contains a configurable debounce circuit to prevent
false triggering. Three levels of debounce protection
are available. See section 6.4.6.
3.1.5 2-wire proxi ity detector input
Most intrinsically safe NAMUR 2- ire proximity
detectors may be connected to the BA377E sensor
input, providing the input safety parameters of the
proximity detector are equal to or greater than the
output safety parameters of a BA377E input. i.e.
Ui ≥ 10.5V dc
Ii ≥ 8.2mA dc
Pi ≥ 25mW
and the minimum operating voltage of the proximity
detector is less than 7.5V. The proximity detector
must be located in the same hazardous area as the
BA377E.
The BA377E contains a configurable debounce
circuit to prevent false triggering of the instrument.
Three levels of debounce protection are available.
See section 6.5.6.
3.1.6 Magnetic pick-off input
CoiL in the input configuration menu is a lo level
voltage input intended for use ith an intrinsically
safe magnetic pick-off sensor hich is not suitable
for controlling the BA377E.

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3.1.7 Voltage input
T o voltage input ranges are independently
selectable in the BA377E Timer configuration menu,
VoLt5 L and VoLt5 H. When configured for either of
the voltage ranges, the input terminals 5 & 6 comply
ith the requirements for simple apparatus. This
allo s the input to be connected to any certified
intrinsically safe voltage source located ithin the
same hazardous area as the BA377E having output
parameters equal to or less than:
Uo ≤ 28V dc
Io ≤ 200mA dc
Po ≤ 0.84W
The BA377E Timer may therefore be directly
connected to and controlled by most certified
intrinsically safe high level voltage signals.
The maximum permitted cable parameters ill be
defined by the intrinsic safety certification of the
voltage source less the BA377E input parameters
hich are small and can often be ignored.
The BA377E contains a configurable debounce
circuit to prevent false triggering of the instrument.
Three levels of debounce protection are available.
See section 6.5.6.
3.1.8 Re ote reset
Connecting the external reset terminals RS1 and
RS2 together ill reset the BA377E hen configured
as a Timer and synchronise the displayed time hen
configured as a Clock. Remote resetting may be
accomplished by any mechanically operated s itch
located in the same hazardous area as the
instrument providing the s itch and the associated
iring can ithstand a 500V rms insulation test to
earth. No Zener barrier is required.
A BA377E may also be remotely reset from the safe
area. Any s itch may be used but a Zener barrier
is required to transfer the contact closure into the
hazardous area hich may be combined ith the
supply barrier so that only one package is required.
A diode return barrier is not suitable for this
application. Fig 1 illustrates ho a BA377E may be
reset from both the safe and the hazardous area.
Note: When used as a Timer the BA377E may also
be reset from the display mode by operating the
& and push buttons simultaneously for more
than t o seconds. See 6.5.19
3.1.9 Control outputs (optional)
Each of the t o factory fitted optional control outputs
is a galvanically isolated single pole solid state
s itch as sho n in Fig 3. The outputs are polarised
and current ill only flo in one direction. Terminals
A1 and A3 should be connected to the positive side
of the supply.
Ron < 5 + 0.7V
Roff > 1M
Note: Because of the series protection diode some
test meters may not detect a closed alarm output
Fig 3 Equivalent circuit of each control output
Each control output is a separate galvanically
isolated intrinsically safe circuit ith output safety
parameters complying ith the requirements for
simple apparatus. This allo s the control output
terminals A1 & A2 and A3 & A4 to be connected to
almost any intrinsically safe circuit protected by a
Zener barrier having output parameters equal to or
less than:
Uo ≤ 28V
Io ≤ 200mA
Po ≤ 0.84W
The maximum equivalent capacitance and
inductance bet een each set of control output
terminals is:
Ci = 22nF
Li = 8µH
To determine the maximum permissible cable
parameters Ci and Li of the BA377E should be
subtracted from the maximum permitted external
capacitance Co and inductance Lo specified by the
certificate for the Zener barrier po ering the circuit
as sho n in Fig 4. The internal capacitance and
inductance of other devices in the loop, such as the
solenoid valve in Fig 4, should also be subtracted
from Co & Lo.

11
Fig 4 Typical control output application
3.2 Use with Galvanic Isolators
Galvanic isolators are probably the simplest
intrinsically safe interface to install as they provide
isolation and do not require a high integrity earth
connection.
Any galvanic isolator certified for the gas group in
hich the BA377E is installed, ith output
parameters less than the input parameters of the
BA377E having the correct function may be used.
Fig 5 BA377E used ith galvanic isolators
Fig 5 illustrates the basic circuit that is used for all
BA377E installations protected by galvanic isolators.
Alternatively sensors may be located in the safe
area. Fig 6 sho s ho an additional galvanic
isolator is used to transfer the sensor output to the
BA377E in the hazardous area, although it may be
difficult to find isolators for some types of sensor.
The BA377E external input conditioning link should
be positioned to suite the output of the galvanic
isolator not the sensor.

12
Fig 6 BA377E Timer used ith galvanic isolators
ith input sensor in safe area.
3.2.1 Power supply
The BA377E requires a minimum of 10V bet een
terminal 1 & 2 and consumes:
10mA ithout optional backlight
plus 22mA ith optional backlight
plus 6mA hen terminals 3 & 4 are linked
Any galvanic isolator certified for the gas group and
Zone in hich the BA377E is installed may be used
to po er the instrument. The output safety
parameters of the isolator must be equal to or less
than the input safety parameters of terminals 1 & 2
and the voltage at terminals 1 & 2 must be greater
than 10V. These requirements are not restrictive
and allo a ide range of galvanic isolators, such as
solenoid drivers, to be used.
3.2.2 Sensor inputs
As sho n in Fig 5 the BA377E input can be directly
connected to hazardous area sensor, or to safe area
sensors via isolators as sho n in Fig 6. Galvanic
isolators are not required in series ith the inputs if
the intrinsically safe sensor is located ithin the
same hazardous area as the BA377E. The input
must be maintained, not momentary,
The BA377E may be used ith a ide variety of
sensors, the follo ing table sho s the s itching
thresholds for each type. For reliable operation the
input signal must fall belo the lo er threshold and
rise above the upper threshold.
Sensor Switching thresholds
Lower Upper
Low voltage range 1.0V 3.0V
High voltage range 3.0V 10.0V
Proxi ity detector 1.2mA 2.1mA
Switch 1001000
Open collector 2k10k
S itch contacts, proximity detectors and open
collector sensors require energising hich is
achieved by linking t o BA377E terminals together
as described in section 2.5.
3.2.3 Switch contact input
Any mechanically activated s itch contact may be
directly connected to input terminals 5 & 6 providing
the s itch is located in the same hazardous area as
the BA377E, and the s itch and associated iring
can ithstand a 500V rms insulation test to earth.
Most magnetically activated industrial push buttons
and reed relays comply ith these requirements.
The BA377E contains a configurable debounce
circuit to prevent false triggering of the instrument.
Three levels of debounce protection are available.
See section 6.5.6
3.2.4 Open collector input
Any open collector sensor located in the same
hazardous area as the BA377E, such as a
mechanically activated opto-isolator, may be directly
connected to input terminals 5 & 6. The sensor and
the associated iring must be able to ithstand a
500V rms insulation test to earth.
The BA377E contains a configurable debounce
circuit to prevent false triggering. Three levels of
debounce protection are available See section 6.5.6

13
3.2.5 2-wire proxi ity detector input
Most intrinsically safe NAMUR 2- ire proximity
detectors may be connected to the BA377E input,
providing the input safety parameters of the proximity
detector are equal to or greater than the output
safety parameters of a BA377E input. i.e.
Ui ≥ 10.5V dc
Ii ≥ 8.2mA dc
Pi ≥ 25mW
and the minimum operating voltage of the proximity
detector is less than 7.5V. The proximity detector
must be located in the same hazardous area as the
BA377E.
The BA377E contains a configurable debounce
circuit to prevent false triggering of the instrument.
Three levels of debounce protection are available.
See section 6.5.6
3.2.6 Magnetic pick-off input
CoiL in the input configuration menu is a lo level
voltage input intended for use ith an intrinsically
safe magnetic pick-off sensor hich is not suitable
for controlling a BA377E.
3.2.7 Voltage input
T o voltage input ranges are independently
selectable in the BA377E configuration menu, VoLt5
L and VoLt5 H. When configured for either of the
voltage ranges, the input terminals 5 & 6 comply
ith the requirements for simple apparatus. This
allo s the inputs to be connected to any certified
intrinsically safe voltage source ithin the same
hazardous area as the BA377E having output
parameters equal to or less than:
Uo ≤ 28V dc
Io ≤ 200mA dc
Po ≤ 0.84W
The BA377E Timer may therefore be directly
connected to and controlled by most certified
intrinsically safe high level outputs.
The maximum permitted cable parameters ill be
defined by the intrinsic safety certification of the
voltage source less the BA377E input parameters
hich are small and can often be ignored.
The BA377E contains a configurable debounce
circuit to prevent false triggering of the instrument.
Three levels of debounce protection are available.
See section 6.5.6
3.2.8 Re ote reset
Connecting the external reset terminals RS1 and
RS2 together ill reset the BA377E hen configured
as a Timer and synchronise the displayed time hen
configured as a Clock. Remote resetting may be
accomplished by any mechanically operated s itch
located in the same hazardous area as the
instrument providing the s itch and the associated
iring can ithstand a 500V rms insulation test to
earth. No galvanic isolator is required.
A BA377E may also be remotely reset or
synchronised from the safe area. Any s itch may
be used but a galvanic isolator or IS relay is required
to transfer the contact closure into the hazardous
area. Fig 5 illustrates ho a BA377E Timer may be
reset from both the safe and the hazardous area.
Note: The BA377E can also be configured to reset
hen the & and push buttons are operated
simultaneously in the display mode for more than
three seconds - see 6.5.19

14
3.2.9 Control outputs - optional
Each of the t o factory fitted optional control outputs
is a galvanically isolated single pole solid state
s itch as sho n in Fig 7. The outputs are polarised
and current ill only flo in one direction. Terminals
A1 and A3 should be connected to the positive side
of the supply.
Ron = less than 5 + 0.7V
Roff = greater than 1M
Note: Because of the series protection diode some
test meters may not detect a closed alarm
output
Fig 7 Equivalent circuit of each control output
Each control output is a separate galvanically
isolated intrinsically safe circuit ith output safety
parameters complying ith the requirements for
simple apparatus. This allo s the control output
terminals A1 & A2 and A3 & A4 to be connected to
almost any certified intrinsically safe circuit protected
by a galvanic isolator providing the isolator has the
correct function and the output parameters do not
exceed:
Uo ≤ 28V
Io ≤ 200mA
Po ≤ 0.84W
The maximum equivalent capacitance and
inductance bet een each set of alarm terminals is:
Ci = 22nF
Li = 8µH (Effectively 0)
To determine the maximum permissible cable
parameters Ci and Li, plus those for any other
intrinsically safe instruments in the loop, should be
subtracted from the maximum permitted external
capacitance Co and inductance Lo specified by the
certificate for the galvanic isolator po ering the
circuit as sho n in Fig 8.
Fig 8 Typical control output application

15
4. INSTALLATION
4.1 Location
The BA377E has a robust glass reinforced Noryl
enclosure ith a toughened glass indo . The front
has IP66 ingress protection and a gasket seals the
joint bet een the instrument enclosure and the
panel, the rear of the instrument has IP20 ingress
protection.
The BA377E may be installed in any panel providing
that the operating temperature is bet een -40°C and
+70°C and the intrinsic safety requirements are
complied ith. At temperatures belo -20°C the
display ill become increasingly slo ith reduced
contrast but the instrument ill continue to function
normally.
Fig 9 sho s the overall dimensions of the instrument
together ith the recommended panel cut-out
dimensions. To achieve an IP66 seal bet een the
instrument enclosure and the instrument panel the
smaller tolerance aperture must be used.
Although the front of the BA377E has IP66 protection
it should be shielded from continuous direct sunlight
and severe eather conditions.
4.2 EMC
The BA377E complies ith the requirements of the
European EMC Directive 2014/30/EU. For specified
immunity all iring should be in screened t isted
pairs, ith the screens earthed at one point ithin
the safe area.
Reco ended panel cut-out
di ensions for all installations
Mandatory to achieve an IP66 seal
bet een instrument and panel
90 +0.5/-0.0 x 43.5 +0.5/-0.0
DIN 43700
92.0 +0.8/ -0.0 x 45 +0.6 -0.0
Support panel iring to prevent vibration damage
Note: Optional backlight is internally po ered
Fig 9 BA377E dimensions & terminals

16
4.3 Installation Procedure
a. Cut the specified aperture in the panel. To
achieve an IP66 seal bet een the instrument
enclosure and the instrument panel the
aperture must have the tighter tolerances
specified in Fig 9.
b. Slide the gasket over the body of the BA377E
before inserting the instrument into the panel
aperture.
c. Firstly ensure that both the panel mounting
clamps are closed by turning the knurled
scre s fully anti clock ise until the t o pips in
the clamp foot align ith holes in the clamp
body.
d. Place a clamp in the recess on each side of the
instrument, pulling gently to slide it onto the
dovetail as sho n in Fig 10. Push the knurled
scre slightly for ard to engage the thread and
tighten by turning clock ise until it is just finger
tight. When the clamps are fitted ensure that
the gasket behind the front panel bezel is
correctly positioned before fully tightening the
clamps to secure the instrument. The maximum
recommended clamp tightening torque is
22cNm (1.95 lbf in) hich is approximately
equivalent to finger-tight plus one half turn.
Do not over tighten.
e. Connect the panel iring to the rear terminal
block(s) as sho n in Fig 9. To simplify
installation, the terminals are removable so that
the panel iring can be completed before the
instrument is installed. In areas subject to
vibration iring should be secured to prevent
damage to the connectors.
Fig 10 Fitting panel mounting clamps
4.4 Scale card
The BA377E's units of measurement are sho n on a
printed scale card in a indo at the right hand side
of the display. The scale card is mounted on a
flexible strip that is inserted into a slot at the rear of
the instrument as sho n in Fig 11. Thus the scale
card can easily be changed ithout removing the
BA377E from the panel or opening the instrument
enclosure.
Ne instruments are supplied ith a printed scale
card sho ing the requested units of measurement, if
this information is not supplied hen the instrument
is ordered a blank card ill be fitted.
A pack of self-adhesive scale cards printed ith
common units of flo measurement is available as
an accessory from BEKA associates. Custom
printed scale cards can also be supplied - see 5.3
To change a scale card, unclip the tapered end of the
flexible strip at the rear of the instrument by gently
pushing it up ards and pulling it out of the
enclosure. Peel the existing scale card from the
flexible strip and replace it ith a ne printed card,
hich should be aligned as sho n belo . Do not fit
a ne scale card on top of an existing card.
Install the ne scale card by gently pushing the
flexible strip into the slot at the rear of the instrument,
hen it reaches the internal end-stop secure it by
pushing the end of the flexible strip do n ards so
that the tapered section is held by the rear panel.
Align the self-adhesive printed scale
card onto the flexible strip and insert
the strip into the instrument as sho n
belo .
Fig 11 Inserting the flexible strip carrying the scale
card into slot at the rear of the instrument.

17
5. ACCESSORIES
5.1 Display backlight
The BA377E Timer and Clock can be supplied ith a
factory fitted backlight that produce green
illumination enhancing display contrast and enabling
it to be read at night or in poor lighting conditions.
The backlight is internally po ered from the
instrument po er supply so no additional iring or
intrinsically safe interface is required, but the supply
current increases as sho n belo .
BA377E Ti er
current
consu ption
Without backlight 10mA
Additional for backlight 22mA
Addition ith terminals 3 & 4 linked 6mA
---------------
Total current 38mA max
BA377E Clock
current
consu ption
Without backlight 10mA
Additional for backlight 22mA
---------------
Total current 32mA max
5.2 Control outputs
Although the dual isolated control outputs are factory
fitted options, they are described in the main body of
this instruction manual as they ill be used for the
majority of applications. If control outputs are
required they should be specified hen the
instrument is ordered.
5.3 Scale card
The BA377E has a indo on the right hand side of
the display through hich a scale card sho ing the
units of measurement such as hours can be seen.
Ne instruments are fitted ith a scale card sho ing
the units of measurement specified hen the
instrument as ordered, if the units are not specified
a blank scale card ill be fitted. A pack of scale
cards pre-printed ith common units of
measurement is available as an accessory. These
can easily be fitted on-site ithout opening the
instrument enclosure or removing it from the panel.
See section 4.4 of this instruction manual.
Custom scale cards for applications requiring less
common units of measurement are also available.
5.4 Tag infor ation
Ne instruments can be supplied ith a tag number
or application information printed onto the rear panel
adjacent to the terminals. This information is not
visible from the front of the instrument after
installation.
5.5 Rear cover sealing kit
The BA377E Timer or Clock’s rear of panel ingress
protection can be increased from IP20 to IP66 ith a
BA495 rear cover sealing kit. Manufactured from 316
stainless steel the cover incorporates t o M20
unthreaded entries for cable glands. It allo s the
BA377E Timer or Clock to be installed in an open
panel, or to provide additional rear protection hen
installed ithin an enclosure.

18
6. OPERATION AS A TIMER
When configured as a Timer the BA377E can
measure and display the elapsed time bet een
external events such as measuring and displaying
ho long machinery is operating. The Timer can be
started and stopped by a remote sensor ith a
continuous output, or from the front panel push
buttons.
The addition of t o optional factory fitted isolated
control outputs allo s the Timer to control external
events such as opening a valve for a predetermined
time. Again the Timer can be started and stopped by
a remote sensor, or from the front panel push
buttons.
When controlling external events the CYCLE function
enables the BA377E Timer to be configured to
repeat the timing period up to 99 times ith a
configurable delay bet een timed periods up to 100
hours or to repeat continuously.
The BA377E may be configured to time-up from zero
to the set time 5Et t, or to time-down from the set
time to zero. The set time may be entered and
displayed in hours, minutes or seconds, or a
combination of units. Elapsed or remaining time is
continuously displayed and a separate display may
be activated to sho the Timer set time 5Et t.
Resetting the timer cycle can be accomplished via
the front panel push buttons or by a remote contact.
A grand total time is maintained hich can be vie ed
by operating the front panel push buttons. It may be
reset to zero from ithin the configuration menu, or
the instrument may be configured to allo resetting
from the front panel push buttons.
Fig 12 sho s a simplified block diagram of the
BA377E hen configured as a Timer. The input can
be configured to accept inputs from a ide variety of
sensors. When the sensor requires energising,
such as a s itch contact, open collector or a t o
ire proximity detector, a link connected bet een
terminals 3 & 4 supplies po er to the sensor input.
The instrument can be supplied ith the follo ing
factory fitted accessories:
Internally po ered Backlight
Dual isolated Control Outputs
The t o factory fitted solid state isolated control
outputs may be independently configured to close
and open at specified parts of the timer cycle, such
as hen the timer starts or finishes.
6.1 Initialisation
Each time po er is applied to a BA377E initialisation
is performed. After a short delay the follo ing
display sequence occurs:
All segments of the display are activated
BA377E is ready to start functioning using
the configuration information stored in the
instrument's permanent memory.
Fig 12 BA377E block diagram ith Timer
configuration.

19
6.2 Controls when configured as a Ti er
The BA377E is controlled and configured via four
front panel push buttons. In the display mode i.e.
hen the instrument is displaying time the push
button functions are:
Push Button Functions
&When local control is enabled starts
the Timer. See 6.5.8
When local control is enabled stops
the Timer. See 6.5.8
) + Sho s the grand total (run time) in
hours and tenths of an hour
irrespective of Timer configuration.
If buttons are held for longer than
ten seconds the grand total may be
reset to zero if the grand total reset
sub-function clr gtot is enabled in
the LoC r5Et configuration function.
See 6.5.20
To reset the grand total to zero from
the display mode press the )
+ buttons for ten seconds until
CLr. no is displayed, using the & or
button change the display to CLr.
YE5 and press ).
& + Resets the Timer to zero or to the
set time 5Et t depending on
hether the Timer is configured to
time-up or time-down hen the t o
buttons are operated
simultaneously for more than t o
seconds. This is a configurable
function. See 6.5.19
( + When enabled in the configuration
menu, operating these t o buttons
simultaneously provides direct
access to the set time 5Et t and
allo s adjustment hen the timer is
in the display mode. See 6.5.15
( + &Sho s in succession, firm are
version number, instrument function
elap5e and any output accessories
that are fitted:
-A Dual Control Outputs
( + )Access to configuration menu

20
6.3 Displays when configured as a Ti er
The BA377E has t o digital displays and associated
annunciators as sho n on page 1.
Elapsed time The upper display sho s the
elapsed time since the Timer
as started hen timing-up from
zero and the remaining time
hen timing-down from the set
time. The display may be
formatted as hh:mm:ss; hh:mm;
mm:ss or ss.
Lower display The display options available on
the lo er display depend on
hether the Timer repeat cycle
function CYCLE5, hich can
repeat the timing period up to 99
times, or continuously ith a
configurable delay bet een
periods, is enabled.
CYCLE5 disabled
The lo er display sho s the set
time 5ET t, or the lo er display
may be disabled if not required.
See 6.5.7
CYCLE5 enabled
The lo er display sho s the
total number of repeat cycles
requested together ith the
number of the current cycle.
Each operation may be briefly
named at it's start or periodically
throughout the cycle.
The lo er display may also be
disabled if not required.
See 6.5.7
Reset Activated hile elapsed time is
annunciator being reset to zero or to the set
time 5ET t.
Grand total Activated hen the grand total
annunciator time is being sho n on the upper
display.
Control output Sho status of each optional
annunciators control output.
'1' and '2'.
6.4 Ti er structure
Fig 13 illustrates the Timer structure and function as
state diagram. It applies hen the instrument is
measuring the time bet een events or is controlling
external events.
The circles in Fig 13 represent the five Timer states,
Reset, Running, Restart-delay, Paused and
Complete. The lines bet een the circles represent
the event required to move the Timer bet een
states. e.g. to initiate timing the Timer is moved
from the Reset state to the Running state by a start
event. This could be an input signal or operation of
the & button. Similarly, to pause the Timer hile it
is timing, the Timer must be moved from the
Running state to the Pause state by a stop event
hich could be an input or operation of the
button.
Reset: re5et
In this state the Timer is readied for operation.
The Timer is stopped and loaded ith zero for
timing-up to the set time 5Et t, or the set time
5Et t for timing-do n.
Running: run
Entered by a start event from the Reset or
Paused states. The Timer times-up to 5et t
or times-do n from 5et t to zero depending
upon it's configuration.
Paused: pau5ed
Entered by a stop event from the Running or
Restart-delay states. Timer is stopped, a start
event returns the timer to it's previous state.
Restart-delay: delay
This state is only accessed hen the Timer
has been configured to repeat the timing cycle
a specified number of times or continuously.
The Restart-delay state is entered
automatically hen the set time 5et t has
been completed. At the end of the delay time
the Timer automatically returns to the Running
state.
Note: When the Timer leaves the Running
state for the last time, it moves to the
Complete state as there is no Restart-delay in
the last timing cycle.
Co plete: done
Entered automatically from the Running state
hen 5et t has been completed and there are
no more cycles to perform.
When the CYCLE5 function is enabled the timing cycle
can be specified to repeat up to 99 times, or can
be configured to repeat continuously.
BEKA Application Guide AG374 contains more
information about the Timer structure.