BEKA BR385 Intrinsically Safe Sounder Instruction Manual

: June 9, 2024
: BEKA

BEKA BR385 Intrinsically Safe Sounder

The BR385 Sounder is CE marked to show compliance with the European Explosive Atmospheres Directive 2014/34/EU and the European EMC Directive 2014/30/EU.
The BR385 is also UKCA marked to show compliance with UK statutory requirements Equipment and Protective Systems Intended for Use in Potentially Explosive Atmospheres Regulations UKSI 2016:1107 (as amended) and with the Electromagnetic Compatibility Regulations UKSI 2016:1091.

INTRODUCTION

The BR385 is a third generation IECEx, ATEX, UKCA and FM certified intrinsically safe sounder that produces a loud warning signal in a hazardous area. Forty nine different first stage alarm sounds can be selected by internal switches and each one can be externally changed to a second or third stage alarm sound. For ATEX and IECEx installations the sounder can be used in all gas groups and may be powered from a BA386 LED flashing beacon, allowing a combined audible and visual alarm to be constructed.

DESCRIPTION

Fig 1 shows a simplified block diagram of a BR385 sounder. The device operates immediately power is applied to the + and – terminals which are duplicated to allow a second sounder to be connected in parallel, or for an end of line monitoring resistor to be installed. The output tone is defined by the position of the six internal switches and this tone can be changed to a second or third stage alarm tone by connecting terminals S2 or S3 to the – terminal of the sounder. The tone generator is crystal controlled to ensure that when two sounders are started at the same time their output tones remain synchronised.

SUPPLY VOLTAGE

For hazardous area installations, BR385 sounders must be powered from a certified Zener barrier or galvanic isolator that will supply between 8 and 28V at the + and – terminals of the sounder.
Sounders may be tested or used in safe areas without a Zener barrier or galvanic isolator, but at supply voltages above 16V the internal current limit will function and the audio output will be reduced. Direct connection to supplies up to 28V of either polarity will not damage the sounder, but it is recommended that without a Zener barrier or galvanic isolator sounders are not operated continuously with a direct supply greater than 16V.

BEKA-BR385-Intrinsically-Safe-Sounder-fig-2

ATEX & UKCA INTRINSIC SAFETY CERTIFICATION

ATEX and UKCA certificates

The BR385 sounder has been issued with an EU-Type Examination Certificate Sira06ATEX2032X. This has been used to confirm compliance with the European ATEX Directive for Group II, Category 1G equipment. See EU Declaration of Conformity for confirmation of compliance with current harmonised standards.
The sounder carries the Community Mark and subject to local codes of practice, may be installed in any of the EEA member countries.

BEKA-BR385-Intrinsically-Safe-Sounder-fig-3

The BR385 sounder has also been issued with a UKCA certificate CSAE 22UKEX1314X which has been used to confirm compliance with UK statutory requirements Equipment and Protective Systems Intended for Use in Potentially Explosive Atmospheres Regulations UKSI 2016:1107 (as amended). See UK Declaration of Conformity for confirmation of compliance with current harmonised standards.
This instruction sheet describes installations which conform with EN 60079-14 Electrical installations design, selection and erection. When designing systems the local Code of Practice should be consulted.

BEKA-BR385-Intrinsically-Safe-Sounder-fig-4

Both the ATEX and UKCA certificates have an ‘X’ suffix indicating that the following special conditions for safe use apply. Practical implications are explained in later sections of this instruction sheet.

SPECIAL CONDITIONS FOR SAFE USE

The equipment has an ingress protection rating of IP66. However, if it has been supplied without cable entry devices, then the user shall ensure that the devices that are fitted will provide an ingress protection that is appropriate to the environment in which it is installed i.e. IP20 or greater.
The total capacitance connected to terminals + w.r.t. – (i.e. the capacitance of the cable plus any other capacitance) shall not exceed 83nF.
The equipment shall not be directly installed in any process where its enclosure might be electro-statically charged by the rapid flow of a non-conductive media.
The equipment shall only be supplied via Terminals + w.r.t. Terminals – from a barrier having a maximum open circuit voltage Uo that is < 28V and a maximum short circuit current Io that is < 93mA, where Io is resistively limited. The barrier or galvanic isolator shall be ATEX or UKCA certified by a notified or Approved body.

Zones, Gas Groups and T rating

The BR385 sounder has been certified:
- Ex ia IIC T4 Ga
- Ta = -40ºC ≤ +60ºC
When connected to approved Zener barriers or galvanic isolators 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, it will only exist for a short time.
  Warning Do not install the BR385 where it may accumulate an electrostatic charge from a rapid flow of dry air.
Be used with gases in groups:
- Group A propane
- Group B ethylene
- Group C hydrogen
In gases that may be used with equipment having a temperature classification of:
- T1 450ºC
- T2 300ºC
- T3 200ºC
- T4 135ºC

Terminals + and –

Power is supplied to the sounder via terminals + and – which have the following maximum input safety parameters:
- Ui = 28V
- Ii = 93mA dc
- Pi = 0.66W
BR385 sounders may be powered from any ATEX or UKCA Ex ia IIC certified Zener barrier or galvanic isolator having output parameters equal to, or less than, these limits. e.g. a certified 28V, 93mA, 0.66W Zener barrier or isolator may be used.
The BR385 ATEX and UKCA certificates specify that the maximum permitted total capacitance that may be connected between the + and – terminals shall not exceed 83nF, irrespective of the Zener barrier or galvanic isolator powering the sounder. This total capacitance includes the cable capacitance plus the capacitance of any other connected device. This should not be restrictive unless the sounder and the barrier or isolator are a long way apart. Single pair instrumentation cables have a typical capacitance of 100pF/metre rising to 350pF/metre for multicore cables and are unlikely to exceed 600pF/metre allowing a cable length of up to 830, 230 or 138 metres respectively.
Up to three BR385 sounders may be connected in parallel and powered from a common barrier or isolator providing the voltage between the + and – terminals does not fall below 8V. Connecting two sounders in parallel will reduce the output from each sounder by about 3dB. Three sounders should only be powered from a common supply when the maximum supply voltage is available.

Terminals S2 and S3

When terminals S2 or S3 are connected to 0V ( – terminal) the sounder output tone changes to the second or third stage alarm respectively. The input safety parameters for these terminals are:
- Ui = 28V
- Ii = 0mA
Therefore for control from the safe area terminals S2 & S3 may only be connected to a certified diode return barrier, or the contacts of a certified intrinsically safe relay. For functional reasons diode return barriers with a voltage drop of less than 0.9V must be used. The maximum permitted cable capacitance Co will be specified on the diode return barrier ATEX certificate, but again should not be restrictive.
For control from the hazardous area terminals S2 & S3 may be directly connected to a mechanically operated switch in the hazardous area complying with the requirements for simple apparatus as defined in EN 60079-11. i.e. having IP20 protection and able to withstand a 500V rms insulation test to earth for one minute.

INSTALLATION

BR385 sounders should only be installed by trained competent personnel.

Mounting
The BR385 sounder may be secured to any flat surface using the two fixing slots. The enclosure provides IP66 protection and is suitable for installation in sheltered exterior locations providing it is positioned so that water can not collect in the horn, and the cable entry is sealed.

Installation procedure

Secure the BR385 sounder to a flat surface via the two fixing slots in the mounting feet.
Remove the front of the sounder by unscrewing the four captive corner screws and pulling the front away from the enclosure.
Fit an appropriate 20mm cable gland or conduit entry into the tapped hole in the enclosure and connect the field wiring to the appropriate sounder terminals as shown in Fig 3. The power supply terminals + and – are duplicated so that sounders may be connected in parallel, or an end-of-line monitoring resistor may be fitted.
Select the required output tone by positioning the six switches as shown in Table 1 and Fig 3.
Apply power to the sounder and adjust the internal volume control to provide the required sound level.
Replace the front of the sounder and tighten the four corner screws.

CAUTION
To avoid a possible electrostatic charge only clean BR385 sounder with a damp cloth.

ELECTRICAL SYSTEM DESIGN FOR INSTALLATION IN HAZARDOUS AREAS USING ZENER

BARRIERS

Single stage alarm

If the control switch is in the positive supply, or the power supply is being turned on and off, only a single channel Zener barrier is required as shown in Fig 4. This circuit may also be used if the sounder is being controlled from the hazardous area by a mechanically activated switch complying with the requirements for simple apparatus. as defined by EN 60079-11. i.e. having IP20 protection and able to withstand a 500V rms insulation test to earth for one minute.

BEKA-BR385-Intrinsically-Safe-Sounder-fig-9

If the negative side or the power supply and one side of the control switch are earthed, the circuit shown in Fig 5 may be used.

BEKA-BR385-Intrinsically-Safe-Sounder-fig-10

Multi-stage alarm
Connecting terminal S2 to 0V activates the second stage alarm, and similarly terminal 3 for the third stage alarm. Fig 6 shows how diode return barrier(s) may be used to control the sounder from the safe area. If only two stages of alarm are required the third stage barrier should be omitted, the 28V 93mA barrier and the single diode return channel may then be contained in one package.

BEKA-BR385-Intrinsically-Safe-Sounder-fig-11

ELECTRICAL SYSTEM DESIGN FOR INSTALLATION IN HAZARDOUS AREAS USING

GALVANIC ISOLATORS.

Galvanic isolators although more expensive than Zener barriers, do not require a high integrity earth connection. For small systems where a high integrity earth is not already available, the use of galvanic isolators often reduces the overall installation cost and simplifies design.

Single stage alarm
BR385 sounders may be powered by any Ex ia ATEX certified galvanic isolator having output parameters within the limits specified in section 4.3. The sounder may be controlled by turning the galvanic isolator on and off, or from the hazardous area by a mechanically activated switch complying with the requirements for simple apparatus as defined by EN 60079-11. i.e. having IP20 protection and able to withstand a 500V rms insulation test to earth for one minute.

BEKA-BR385-Intrinsically-Safe-Sounder-fig-12

Multi-stage alarm
Fig 8 shows a typical application in which the first and second stage alarm tones are activated by the alarm outputs of a BA327E intrinsically safe loop powered indicator. The BA327E alarm outputs have been certified as simple apparatus and may therefore be used to switch the BR385 sounder in the hazardous area. The contacts of most certified intrinsically safe relays may also be used in the same way.

BEKA-BR385-Intrinsically-Safe-Sounder-fig-13

ACCESSORIES

Tag number
BR385 sounders can be supplied identified by a tag number thermally printed on a self adhesive label.

SERVICING

No attempt should be made to repair a faulty BR385 sounder. Suspect sounders should be returned to BEKA associates or your local agent for repair.

GUARANTEE

Sounders which fail within the guarantee period should be returned to BEKA associates or your local agent. It is helpful if a brief description of the fault symptoms is provided.

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.

Tone Number

| |

Switch Settings

1 2 3 4 5 6

|

Second Stage

Alarm

|

Third Stage

alarm

---|---|---|---|---

Tone 1

|

Continuous 340Hz

|

0 0 0 0 0 0

|

Tone 2

|

Tone 5

APPENDIX 1

Installation in USA

Factory Mutual Certification
- For installations in the USA the BR385 sounder has the following FM intrinsic safety certification;
- CLI; Div 1; Gp A, B, C & D T4 Ta = 60°C Entity IP66
- CLI; Zone 0; AEx ia IIC T4 Ta = 60°C Entity IP66
- The FM Certificate of Compliance 3027157 and the associated Control Drawing CI385-32 may be downloaded from the BEKA website www.beka.co.uk.
Divisions / Zones, Gas Groups and T rating
- The BR385 sounder has been approved intrinsically safe by FM for installation in the following Divisions / Zones and used with the following hazards.
- Installation in:
- Division 1 Ignitable concentrations of flammable gases, vapours or liquids can exist all of the time or some of the time under normal operating conditions.
- Division 2 Ignitable concentrations of flammable gases, vapours or liquids are not likely to exist under normal operating conditions.
- 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, it will only exist for a short time.
- Use with gases in groups:
- Group A Acetylene
- Group B Hydrogen
- Group C Ethylene
- Group D Propane
- IIA Propane
- IIB Ethylene
- IIC Hydrogen
- Having a temperature classification of:
- T1 450ºC
- T2 300ºC
- T3 200ºC
- T4 135ºC
  at an ambient temperature between -20ºC and +60ºC
Intrinsic safety parameters
The BR385 sounder has been assessed using the entity concept and the FM safety parameters are identical to the ATEX, UKCA and IECEx safety parameters except that output parameters Uo, Io and Po are specified for the two tone changing terminals S2 and S3. Uo limits the maximum cable capacitance to 390nF in gas group B and IIC (hydrogen) when the terminals are connected to an isolated contact. This is unlikely to be restrictive. Uo is unlikely to reduce the permitted cable capacitance when the terminals are connected to a diode return barrier or galvanic isolator in the safe area, but Io should be considered when determining the maximum permitted cable inductance, but again is unlikely to be restrictive.

APPENDIX 2

IECEx certification

The IECEx Certification Scheme
IECEx is a global certification scheme for explosion protected products which aims to harmonise international certification standards.
IECEx Certificate of Conformity
- The BR385 sounder has been issued with an IECEx Certificate of Conformity number IECEx SIR 17.0014X which specifying the following certification code:
- Ex ia IIC T4 Ga -40ºC ≤ Ta ≤ +60ºC.
- The IECEx certificate may be downloaded from BEKA website www.beka.co.uk, or requested from the BEKA sales office.
Installation
The IECEx intrinsic safety parameters are identical to the ATEX safety parameters described in the main section of this manual and both refer to the same standards. Therefore the ATEX installation requirements specified in this manual also apply for IECEx installations, but the local code of practice should also be consulted.
Special conditions for safe use
The IECEx certificate has an ‘X’ suffix indicating that special conditions apply to prevent an electrostatic charge developing on the outside of the instrument enclosure – see section 4.1.
CAUTION
To avoid a possible electrostatic charge only clean BR385 sounder with a damp cloth.