Single Gas Detection System MANUAL.pdf · 2019. 7. 24. · RY1 RY2 RY3 A1 A2 FAULT NO1 CM NC1 NO2...

B-I INDUSTRIAL CO., LTD.

SINGLE GAS DETECTION SYSTEM

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Single Gas Detection System

Operation & Maintenance

Manual



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REVISION RECORD

Description Of Change Pages

1 SPECIFICATION ---------------------------------------------------------------------- 6

2. INTRODUCTION ---------------------------------------------------------------------- 8

3. BASIC OPERATION ----------------------------------------------------------------- 12

4. OPERATION & SETTING ---------------------------------------------------------- 17

5. INSTALLATION ----------------------------------------------------------------------- 25

6. CABLING ------------------------------------------------------------------------------- 27



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TABLE OF CONTENTS

INDEX PAGES 1. SPECIFICATION ------------------------------------------------------------------------------------------ 6 1. ESTABLISHMENT --------------------------------------------------------------------------------------------- 6

2. SPECIFICATION ----------------------------------------------------------------------------------------------- 7

2. INTRODUCTION ------------------------------------------------------------------------------------------ 8 1. MAIN ELEMENTS --------------------------------------------------------------------------------------------- 8 2. OXYGEN DEFICIENCY -------------------------------------------------------------------------------------- 8 3. STATUS MODULE --------------------------------------------------------------------------------------------- 9 4. RELAY OUTPUTS --------------------------------------------------------------------------------------------- 9 5. ANALOGUE OUTPUTS -------------------------------------------------------------------------------------- 10 6. FLOW SWITCH INPUT -------------------------------------------------------------------------------------- 10 7. SERIAL INTERFACE (Option) ------------------------------------------------------------------------------ 11

3. BASIC OPERATION ----------------------------------------------------------------------------------- 12 1. SYSTEM OPERATION --------------------------------------------------------------------------------------- 12 2. ALARM OPERATION ----------------------------------------------------------------------------------------- 12 3. SWITCHING THE SGDS ON ------------------------------------------------------------------------------- 13 3-1. Switch Operation ------------------------------------------------------------------------------------------ 14 3-1-1. External Switch Operation ---------------------------------------------------------------------------- 14 3-1-2. Internal Switch Operation ----------------------------------------------------------------------------- 14 3-2. Alarm: Calibration Operation ---------------------------------------------------------------------------- 14 4. SENSORS ------------------------------------------------------------------------------------------------------- 15 4-1. Oxygen Sensor --------------------------------------------------------------------------------------------- 15 4-2. Alarm Indication -------------------------------------------------------------------------------------------- 15 4-3. Relay Contacts --------------------------------------------------------------------------------------------- 15 4-4. Relay Status ------------------------------------------------------------------------------------------------- 15 4-5. Alarm Relays ------------------------------------------------------------------------------------------------ 15 4-6. Fault Detection --------------------------------------------------------------------------------------------- 16 4-7. Fault Relay -------------------------------------------------------------------------------------------------- 16 4-8. Fault Inhibit -------------------------------------------------------------------------------------------------- 16



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INDEX PAGES

3. OPERATION & SETTING --------------------------------------------------------------------------- 17 1. NORMAL mode ------------------------------------------------------------------------------------------------ 17 2. CALIBRATION mode ----------------------------------------------------------------------------------------- 18 2-1. ZERO --------------------------------------------------------------------------------------------------------- 18 2-2. SPAN --------------------------------------------------------------------------------------------------------- 19 3. ALARMS mode ------------------------------------------------------------------------------------------------- 20 4. SETUP mode --------------------------------------------------------------------------------------------------- 20 4-1. SAMPLE MODE ------------------------------------------------------------------------------------------- 21 4-1-1. DEFFUSION --------------------------------------------------------------------------------------------- 21 4-1-2. PUMPED -------------------------------------------------------------------------------------------------- 21 4-2. CAL PERIOD ------------------------------------------------------------------------------------------------- 22 5. CLOCK mode --------------------------------------------------------------------------------------------------- 22 6. OUTPUT mode ------------------------------------------------------------------------------------------------- 23 7. SET PASSWORD mode ------------------------------------------------------------------------------------- 24

4. INSTALLATION ------------------------------------------------------------------------------------------- 25 1. GENERAL ------------------------------------------------------------------------------------------------------- 25 1-1. Control Unit ------------------------------------------------------------------------------------------------- 25 1-2. Detection Head --------------------------------------------------------------------------------------------- 25 1-3. Location ------------------------------------------------------------------------------------------------------ 25 1-4. Fixing --------------------------------------------------------------------------------------------------------- 25

2. CONTROL UNIT ----------------------------------------------------------------------------------------------- 26

5. CABLING ---------------------------------------------------------------------------------------------------- 27 1. GENERAL ------------------------------------------------------------------------------------------------------- 27 2. TYPES OF CABLE -------------------------------------------------------------------------------------------- 27 2-1. Mineral Insulated Copper Covered(MICC) ---------------------------------------------------------- 27 2-2. PVC Armoured Cable ------------------------------------------------------------------------------------- 27 3. CABLE SIZE ---------------------------------------------------------------------------------------------------- 27 3-1. Cable Resistance ------------------------------------------------------------------------------------------ 28 3-2. Cable Distance --------------------------------------------------------------------------------------------- 28 3-3. System Noise ----------------------------------------------------------------------------------------------- 28 3-4. Connectings and Earthing ------------------------------------------------------------------------------- 28 4. INSTALLATION ------------------------------------------------------------------------------------------------- 29 4-1. Glanding ----------------------------------------------------------------------------------------------------- 29



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INDEX PAGES

4-2. Tagging ------------------------------------------------------------------------------------------------------- 29 4-3. Insulation & Continuity ----------------------------------------------------------------------------------- 29 4-4. Loop Resistance Test ------------------------------------------------------------------------------------- 29 4-5. Insulation Test ---------------------------------------------------------------------------------------------- 29 5. CONNECTING UP -------------------------------------------------------------------------------------------- 30 5-1. General ------------------------------------------------------------------------------------------------------- 30 5-2. Mains Power PCB ----------------------------------------------------------------------------------------- 30 5-3. Detectors ----------------------------------------------------------------------------------------------------- 31



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1

SPECIFICATION

SPECIFICATION

MODEL : SGDS-2000 2005-06-16

MODEL : SINGLE GAS DETECTION SYSTEM(SGDS-2000)

R

E

V

I

S

O

N

0 2005-06-16 ESTABLISHMENT J.H.

PARK

N. M.

LEE

Y. S.

KIM

ESTABLI-

SHMENT

NO DATE REASON P.I.C INSPECTED

BY

APPROVED

BY



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B-I INDUSTRIAL CO., LTD. PAGE 1 / 1

DESCRIPTION SINGLE GAS DETECTION

SYSTEM

SPECIFICATION ESTABLISHMENT 2005-06-16

MODEL SGDS-2000 CLASSFICATION PRODUCT REVISION 20 . .

1. SPECIFICATION


MODEL SGDS-2000

GAS Oxygen

110 / 220 VAC 50/60Hz POWER SUPPLY

24 VDC ±10% (ripple P-P : max. 5%)

POWER CONSUMPTION MAX. 300 mA (BASED ON 24 VDC, disconnection of the load)

ACCURACY ±1% F.S.D

CURRENT OUTPUT 4 ~ 20 mA

250 VAC : 10 A

R E L A Y OUTPUT 100 VDC : 5 A

LOW ALARM: Configured within 1 ~ 20 % range

A L A R M

CONFIGULATION HIGH ALARM: Configured within 20 ~ 25 % range

INSULATION RESISTANCE Min.100MΩ (at 500VDC, between all terminals and case)

DIELECTRIC STRENGTH 750VAC 50/60Hz for 1 minute (between all terminals and case)

VIBRATION

1.5mm amplitude at frequency of 10~55Hz in each of X,Y,Z

directions for 2 hours

SHOCK MAX. 50 G

AMBIENT TEMPERATURE 5 ∼ 40 ℃

AMBIENT HUMIDITY 5 ∼ 95% RH

LCD 4 Line 20 Digital LCD Display (Backlight)

DISPLAY

LED(4 KINDS) POWER: Green, FAULT: Yellow, A1: Red, A2: Red

DIMENSION H X W X D : 230mm X 170mm X 102mm

PANEL

WEIGHT 3.5 Kg

PROTECTION IP54(IEC specification)

INPUT VOLTAGE 5 VDC ±10% (ripple P-P : max. 5%)

OUTPUT VOLTAGE 0 ~ 3 VDC (Oxygen: 0 ~ 25%)

POWER CONSUMPTION Max. 30 mA

DIMENSION 39Ø X 85.5 mm

S

E

N

S

O

R WEIGHT 0.4 Kg



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2

INTRODUCTION The Single Gas Detection System(SGDS) is a continuous monitoring system de signed for the detection and control of Oxygen deficiency. The unit has been designed to produce a cost effective solution to industrial/co mmercial s afety problems. The unit handles one channel of the abo ve elements and provides audible and visual indication of module st atus and alarms. Relay output s are provided to control external pl ant and analogue output s interface with other e quipment. The system can be operated from 110/220VAC or 24VDC.

1. MAIN ELEMENTS The main elements are contained in a sheet metal case. The SGDS is detected oxygen deficiency. In addition, the LCD display module provides gas level st atus information. A status module gives the indication of power on, alarms, fault s. The f ront panel also has 2 bush buttons to alarms reset and dimmer . The system is primarily mains powered and can be set to 110 or 220V AC befo re leaving the factory (the unit can also be powered from a 24VDC source). If the main power(110 or 220VAC) is no more supplied due to the failu re and problem of electric power supply , 24VDC power is provided automatically . When electric power supply is recovered, the 24VDC will be converted to 110 or 220VAC. The system has voltage free relay contact outputs which can be user configured to be normal opened(N.O) / normal closed(N.C)

2. OXYGEN DEFICIENCY The oxygen deficiency system is used for oxygen measurements in the range 0 to 25%. The system uses an electrochemical sensor.



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3. STATUS MODULE The status module indicates Power On, Fault and Alarms

POWER FAULT A1 A2

Indicates second alarm level

Indicates first alarm level

Indicates fault on head or cable Unit is powered up The LCD di splay shows detailed information, gas reading, time, alarm levels and alarm st atus for each channel.

4. RELAY OUTPUTS Three relay outputs are provided as standard, A1, A2 and Fault. A1 A2 FAULT

NO1 CM NC1 NO2 CM NC2 NO3 CM NC3 A1 Output A2 Output FAULT Output



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5. ANALOGUE OUTPUTS The unit can simultaneously provide 4 to 20mA output. SENSOR OUT FLOW 422 5V Sin GD +mA –mA 5V Fin +422-

4 to 20mA Output

6. FLOW SWITCH INPUT In case that the type of gas sampling is Sample Pump Type, please connect the Flow Switch Input Signal as described below. SENSOR OUT FLOW 422 5V Sin GD +mA –mA 5V Fin +422-

Flow Switch Input



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7. SERIAL INTERFACE (Option) It will be used if interface our instrument with outer instrument by 422. The method of connection is as described below. SENSOR OUT FLOW 422 5V Sin GD +mA –mA 5V Fin +422-

422 Interface



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3

BASIC OPERATION

1. SYSTEM OPERATION The basic system consist s of an a larm module and detect ion head which are conn ected together via main pri nted circuit board(PCB) to provide an indication of gas concentration. Outputs consist of 2 relay alarm outputs, fault relay output, analogue output 4 to 20 mA.

2. ALARM OPERATION The following sections describe the alarm operation for the Single Gas Detection System.

Alarms: Normal Operation When an alarm threshold has been passed, or a module fault has been detected, the appropriate LED on the status module will be i lluminated. A1 and A2 alarm can be programmed to be latchin g or non-latching whilst a fault is non-latching. A sensor fault cannot override an existing alarm.



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3. SWITCHING THE SGDS ON Switch the power on. The POWER LED on the front p anel illuminates, it remains illuminated whi le the ac powe r is co nnected to the un it and swit ched on. The SGDS ente rs its warm-up cycle, this takes approximately 60 seconds to complete. During warm-up the following screens appear on the LCD display. The normal operating display(shown above) is displayed continuously when the warm-up checks are completed successfully. If sensor is not co nnected with Main PCB appropriate ly, Fault Led is twinkled on Front Panel and the me ssage of Sensor is also twinkled on LCD. In this case, please connect Sensor with Main PCB.

B-I INDUSTRIAL

VER 0.0

01/01 00:01 Oxygen : 20.9 %

01/01 00:01

SENSOR

Oxygen : %



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3-1. Switch Operation The Single Gas Detection System has 2 external switches and 5 internal switch.

3-1-1. External Switch Operation The 2 external switches are labeled ALARM RESET and DIMMER. Their operation is as follows: ALARM RESET: The ALARM RESET button clears any alarm conditions that no longer exist. If any alarm condition does still exist when the ALARM RESET button is Pressed the external buzzer is silenced DIMMER: Dimmer Button is used in case of bla ck out and cutting of f the light. If you push Button

once, 4 X LED is not illuminated and if you press one more, the LED will be illuminated.

3-1-2. Internal Switch Operation RESET Switch: The RESET(SW7) switch is a system reset and is equivalent to switching the system off then on MODE Switch: Mode(SW4) switch is u sed for entering to MENU mode from Normal Mode or ch ecking of m ode selected or Returning to prior step without storing. ENTER Switch: Enter(SW1) is used for entering selected mode or modification of value configured and returning to the prior step after storing. UP↑ Switch: UP(SW3) switch is used for moving cursor above when mode is selected. DOWN↓ Switch: DOWN(SW2) switch is used for moving cursor below when mode is selected.

3-2. Alarm: Calibration Operation When the system enters calibration mode the following is performed: All relays switched to their ‘SAFE’ or disabled state. The internal buzzer is silenced.



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4. SENSORS 4-1. Oxygen Sensor The oxygen deficiency sensors are 3 wire devices with a voltage output. The unit is supplied with a const ant voltage from the main board and electrochemical reaction in the detection head cause changes in the DC voltage signal to main PCB which corresponds to t he changes in gas concentration.

4-2. Alarm Indication When the input signal from the detection head exceeds the alarm set point, the LED’s in the status module are illuminated to show that the alarm level has been exceeded.

4-3. Relay Contacts These relays are provi ded with vo lt free change over co ntacts which are brought out onto the terminal blocks on the main board for connection to external control devices.

4-4. Relay Status These relays are shown in all docu mentation in the Normal Close(N.C) position (as is convention). The default configuration for the alarm relays is Normal Close(N.C) under the no alarms condition.

4-5. Alarm Relays In addition to the status module indicators, relays mounted on the main PCB are operated. These relays are user p rogrammable as to oper ational status, that is, n ormal open(N.O) / normal close(N.C) to give fail safe operation.



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RY1 RY2 RY3 A1 A2 FAULT

NO1 CM NC1 NO2 CM NC2 NO3 CM NC3

L N These com mon relays (shown abo ve) have a fixed operation and will switch when their tr igger condition is detected: RY1 (A1): Switches when A1 alarm threshold is exceeded RY2 (A2): Switches when A2 alarm threshold is exceeded RY3 (FAULT): Switches when module or system fault is detected.

4-6. Fault Detection All modules have fault detection circuits which detect faults in the cable between module and head. When this occurs the fault indicator on the status module will illuminate.

4-7. Fault Relay A separate fault relay is provided which is switched when a fault is detected. The default configuration for this relay is normal close(N.C) under correct system operation. This relay can be configured to be normal open(N.O) / normal close(N.C)

4-8. Fault Inhibit When a fault is detected by the module the individual alarm relays are inhibited and thus a fals e alarm is not usually generated under fault conditions.

L N

VISUAL

ALARM

L N

AUDIBLE

ALARM

220VAC

SUPPLY



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4

OPERATION & SETTING Single Gas Detection System(SGDS) consist s of 7 X mode and we would like to describe th e

each functio n of mode and the me thod of setting as follo ws: All setting for each mode can be available with only 4 X inner switches (SW1 ~ SW4) without any support from outer equipments. To prevent from malfunctioning by un authorized person, the function of password is configured and password can be changed by users. (The Factory Default of password is 0000)

1. NORMAL mode On Normal Mode, time and the real time change rate of gas detected are displayed.

ENTER

01/01 00:01 Oxygen : 20.9 %

M E N U → 1. NORMAL

2. CALIBRATE 3. ALARMS



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2. CALIBRATION mode Calibrate mode is used when calibration and it consist s of two kind of st ages, namely Zero a nd Span.

2-1. ZERO Zero Mode is for configuration of Zero when the calibration of SGDS is to be required. You can see

Present Indication as p er ②, if you push Ent er Switch, t he value of 20.9% will be Configu red automatically. (Note: Ze ro Configuration should be done in open sp ace without interference of other gases.)

①

ENTER

②

ENTER

③

M E N U 1. NORMAL

→ 2. CALIBRATE 3. ALARMS

CALIBRATION 1. ESC

→ 2. ZERO 3. SPAN

CALIBRATION ▌▌▌▌▌▌▌ ZERO : 19.9 %

CALIBRATION ▌▌▌▌▌▌▌▌ ZERO : 20.9 %



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2-2. SPAN Span Mode is for the configuration o f Span Value when the calibration of SGDS is to be requested

and present value is displayed as ②. For example, if you inject sen sor module of instrument b y 3.5% calibration gas a nd 4.3% ind ication will b e displayed as per ③, please push DOWN switch and change the value to 3.5% and then push Enter Switch. (Note: When inject the calibration gas, the en ough time for configura tion is requ ired until th e change of indication stops.

①

ENTER

② CALIBRATION GAS INPUT(3.5% O2)

③ DOWN↓

④

ENTER

CALIBRATION 1. ESC 2. ZERO

→ 3. SPAN

CALIBRATION ▌▌▌▌▌▌▌ ZERO : 20.9 %

CALIBRATION ▌▌ ZERO : 4.3 %

CALIBRATION ▌ ZERO : 3.5 %



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3. ALARMS mode Alarms Mod e let s u sers change an d configure Alarm Level of A1 & A2. The initia l value is a s

described on ②, ③ and cursor is twinkled at the position will be changed. If you want to cha nge the configur ed value, p lease pu sh UP or Down Switch to adjust th e positio n of change. The completion of configuration will be done by push Enter Switch.

①

ENTER

②

ENTER

③

ENTER

4. SETUP mode Setup Mode consists of Sample Mode and Cal Period.

M E N U 1. NORMAL 2. CALIBRATE

→ 3. ALARMS

ALARMS

LOW : 19.■% HIGH : 23.0 %

ALARMS

LOW : 19.0 % HIGH : 23.■%

→ 4. SETUP 5. CLOCK 6. OUTPUT 7. SET PASSWORD



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4-1. SAMPLE MODE On Sample Mode, you can select Gas Sampling method.

4-1-1. DIFFUSION If the Sampling Method is Sensor Head Type, please select Diffusion as below.

4-1-2. PUMPED If the gas sampling method is Sample Pump Type, please select PUMPED. There are two types of

input for SAMPL E PUMP namel y ①NORMAL OPE N, ②NORMAL CLOSE a re available. According t o user ’s ap plication, a djust the value by pu shing Down and Up switches and all configuration will done by pushing Enter Switch.

① ENTER ②

ENTER ENTER

SETUP 0. ESC

→ 1. SAMPLE MODE 2. CAL PERIOD

SAMPLE MODE 0. ESC

→ 1. DIFFUSION 2. PUMPED

SAMPLE MODE 0. ESC

1. DIFFUSION → 2. PUMPED

PUMPED 0. ESC

→ 1. NORMAL OPEN 2. NORMAL CLOSE

PUMPED 0. ESC

1. NORMAL OPEN → 2. NORMAL CLOSE



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4-2. CAL PERIOD On Cal Period, the period of calibra tion can be configured. It can be configured by users according to the terms and conditions of Sensor and it can be reduce d and incre ased per 6 months. This configuration can be done by Enter Switch after adjusting it by Up and Down Switch. ENTER

ENTER Once the calibration period is set up, the time will be countable. If the period exceeds to configured period, the following alarm message will be displayed. In this case, please contact us for calibration.

5. CLOCK mode On clock mode, you can configure the present time. To configure the clock, please push Up and Down Switch at the position of cursor

SETUP 0. ESC

1. SAMPLE MODE → 2. CAL PERIOD

CAL PERIOD

PERIOD : 12 M

01/01 00:01 CAL T/O

Oxygen : 20.9 %

4. SETUP → 5. CLOCK

6. OUTPUT 7. SET PASSWORD



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ENTER

6. OUTPUT mode On Output Mode, you can configure the user’s environment for output of 4 to 20mA.

① mode is used for O utput Calibration. The change of th is mode will occur s the malfunction of instrument so it is locked by maker password.

ENTER

①

On ② OUTPUT RANGE, you can configure output range according to user ’s environment in proportion of 4 to 20mA. The config uration will be done by pushing ent ering switch after adjusting by Up and Down Switch.

For example, if you want to configure the range of 2.0 to 30% as shown on ③, 0% to 4mA of gas indication will be displayed and when 30%, 20mA will be displayed.

②

TIME SETTING 2005/06/10 10:30:48

4. SETUP 5. CLOCK

→ 6. OUTPUT 7. SET PASSWORD

OUTPUT 0. ESC

→ 1. OUTPUT CALIBRATE 2. OUTPUT RANGE

OUTPUT 0. ESC 1. OUTPUT CALIBRATE

→ 2. OUTPUT RANGE



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ENTER

③

ENTER

7. SET PASSWORD mode On Set Pas sword Mod e, you can change use r’s p assword. Password should be configured to prevent instrument from malfunction ing due to u nauthorized person’s carelessness and it can b e changed by user. If you want to change p assword, you can input the number at the position of cursor by using UP and Down Switch. By pressing Enter Switch, you can pass to next unit. (Note: The factory default password is 0000)

ENTER

① ENTER

OUTPUT RANGE 1. 0 – 20.9 %

→ 2. 0 - 30 % 3. 0 - 100 %

4. SETUP 5. CLOCK 6. OUTPUT

→ 7. SET PASSWORD

SET PASSWORD PASSWORD : ■000



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5

INSTALLATION

1. GENERAL A successful gas detection system d epends on careful sitin g of detection heads, control unit and cable installation.

1-1. Control Unit The Control Modules must be sited in a safe area and provided with a suitable power supply. Interconnecting cables should comply with the relevant inst allation and safety codes and be in line with good industrial practice.

1-2. Detection Head Consideration must be given to the location of detection heads with particular regard to gas density.

1-3. Location The positioning and number of heads required for a particular installation require the consideration of man y factors. The manufacturer ’s engineers are always available to survey inst allations a nd give advice and recommendations. Every portion of the buiding where there is a p otential hazard should be covered and each effectively enclosed space should be considered separately.

1-4. Fixing Detection head and junction box can be fixed using the mounting bracket provided. Detection heads should be carefully sited and always facing down unless ther e are p articular engineering considerations for other orientation in which case the manufacturer’s advice should be sought.



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2. CONTROL UNIT

WARNING: THE CONTROL UNIT MUST NOT BE INSTALLED IN A HAZARDOUS AREA. IT IS ONLY SUITABLE FOR SAFE AREA LOCATION The equipment should be located in a non-hazardous area which is clean and dry , (that is, th e apparatus shall not be exposed to dripping or splashing) in conditions which are suitable for normal electrical e quipment. Control mo dules shou ld not be lo cated next to electrical plant liab le to generate lar ge electrom agnetic tran sients which might af fect the small in strumentation sign als. Radio transmitters should also be considered f or their interference ef fects. Suitable isolation an d fuse protection circuits may be necessary to give ease of maintenance and servicing



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6

CABLING

1. GENERAL All cabling should be exclusive to th e gas detection system and isolated from other circuit wirin g. Detection system cabling must be sp aced at le ast 60mm from other cir cuits. Cables should be of good quality since ga s detection systems require high inte grity. Various cable type s are available dependent on the industrial location and area classification. All cables should be installed to current Institution of Electrical Engineers practice.

2. TYPES OF CABLE 2-1. Mineral Insulated Copper Covered (MICC) These cables which comply with BS6207 are p articularly suitable for gas alarm inst allations which are not subject to move ment. Where electrolytic corrosion may occur in damp or chemically active environments, a PVC sheathed cable should be provided. Additional mechanical protection may be necessary. Conduit should be scre wed heavy gauge tubing with VRS or PVC ca bles complying with BS6007 or BS6004 with copper conductors.

2-2. PVC Armoured Cable PVC cable with single wire armour and PVC sheath is suit able for use in the se locations. Care should be taken since PVC is vulnerable to att ack by certain organic chemicals. PVC compounds become increasingly brittle and stiff at temperatures below 0℃.

3. CABLE SIZE The cable size is only of major importance to the flammable detection system where the head lin e currents are in the order of 300 to 350mA and the detection head requires 2 to 2.5V to operate correctly. Under these circumstances the h ead line resistance can become a contr olling factor. In the toxic he ad unit the line current is a maximu m of 20mA and therefore line resist andce is n ot a



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major factor in cable size. The flammable control module will drive a line resistance of 20R loop. In the toxic system the maximum line drive cap acity is limited to 500Ω in the signal line and 400Ω in the power line.

3-1. Cable Resistance The resistance of pure annealed copper wire change considerably with temperature.

3-2. Cable Distance Maximum control module/head distance related to cable size for flammable modules are shown in the table below:

Cable Size Resistance Maximum Distance Sq. mm AWG Type Ω / 1000m Miles Metres

0.5 22 16/0.2 40.1 0.15 250

0.75 18 24/0.2 26.7 0.23 370

1.0 16 32/0.2 20.0 0.31 500

1.5 14 30/0.25 13.7 0.45 720

2.5 12 50/0.25 8.21 0.74 1,200

4.0 10 56/0.25 5.09 1.18 1,900

AWG are only approximate equivalents for use with this system.

3-3. System Noise At long distance noise rather than pure line resist ance can affect performance. In those case s the manufacturer should be consulted before installation. If the installation is in a hazard ous location it should comply with the relevant specification, for example, BS5345, CP1003NFP etc.

3-4. Connections and Earthing NOTE: THE CABLE SHOULD CONTAIN THE MINIMUM NUMBER OF JOINTS. ALL CONNECTIONS SHOULD BE TO THE HIGHEST STANDARDS USING ONLY CRIMPED TERMINALS AND CLAMP TYPE TERMINAL BLOCKS. OUTER SCREENS OR ARMOURING SHOULD BE EARTHED ONLY AT THE CONTROL MODULE TO AVOID EARTH LOOPS AND LONGITUDINAL INDUCTION.



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4. INSTALLATION 4-1. Glanding All cables should be secured, clamped and glanded using approved glands to the manufacturer’s specification.

4-2. Tagging Cables should be tagged and identified and all cores identified by suitable means.

4-3. Insulation & Continuity After installation of th e cable and before termination of cores either end of loop, resistance and insulation resistance should be checked.

4-4. Loop Resistance Test Loop resist ance betwe en any 2 cores should not exceed 20 Ω on fla mmable he ad inst allations. Loop resistance between any 2 cores should not exceed 400Ω on toxic head installations.

4-5. Insulation Test Individual cores should be checked between each other and earth to obtain an insulation resistance of greater than 50MΩ when tested with a 500V insulation tester.

CAUTION: IT IS IMPORTANT THAT MODULE AND HEAD ARE DISCONNECTED BEFORE INSUATION TESTS ARE COMMENCED. CARE SHOULD BE TAKEN TO ENSURE NO ABNORMAL VOLTAGES OR CURRENTS ARE SUPPLIED TO HEAD OR MODULES SINCE THIS WILL INVALIDATE THE GUARANTEE. IN HAZARDOUS AREA ONLY AN INTRINSICALLY SAFE INSULATION TESTER SHOULD BE USED.



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5 CONNECTING UP 5-1. General The main connections to the Single Gas Detection System are shown in the block diagram below, these are: 1) Mains connetion – 3 core 2) Head connection – 3 core 3) Relay outputs – as required 4) Analogue outputs – as required These cables are terminated on individual terminal blocks located at the bottom of the Single Gas Detection System PCB or on the power supply terminal block which is located b ehind the main board.

5-2. Mains Power PCB The Mains Power PCB is located behind the main PCB. Th e mains input should be independently isolated and fused external to the Single Gas Detection System. The mains input is hard wired at the factory to be either 1 10V or 22 0V AC 50~60Hz. Connection is via the white fused terminal block mounted on the rear chassis.

SINGLE

GAS

DETECTION

SYSTEM

DETECTION HEAD

ANALOGUE

OUTPUT MAIN INPUT

RELAY OUTPUT



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POWER PCB

F.G AC1 AC2 + 24V - EARTH 24V DC

110/220V AC

5-3. Detectors The detector terminal block is fitted at the bottom of the main PCB and is connected to the sensors by means o f a 3 core cable. The detectors sh ould be mounted using t he B-I INDUSTRIAL CO., LTD. approved head mounting box and the cables terminated on the box terminal strip. The cables should be earthed or screen co nnected at t he p anel e nd only an d in some cases it may be necessary to connect the system 0V to the screen as well. This is particulary the case where long cable lengths are experienced or where high levels of Electromafnetic interference are found. The detection heads are connected to the main PCB terminal block as shown below: SENSOR OUT FLOW 422 5V Sin GD +mA –mA 5V Fin +422-

RED BLUE YELLOW

3A FUSE

POWER

SWITCH



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Different connections are made depending on whether the module is Oxygen. All cables should be ferruled and the use of crimp connections on flexible cables is recommended, but care should be taken in using only goo d quality crimp s and the joint mad e with a cer tified crimp tool, sin ce small resistance changes in the crimp due to poor crimping can faulty operation.

Single Gas Detection System MANUAL.pdf · 2019. 7. 24. · RY1 RY2 RY3 A1 A2 FAULT NO1 CM NC1 NO2...

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Transcript of Single Gas Detection System MANUAL.pdf · 2019. 7. 24. · RY1 RY2 RY3 A1 A2 FAULT NO1 CM NC1 NO2...