GDS 404 Series Operating Handbook Download

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T E C H N O L O G I E S

Technical Sheet

ref C894

EOL

CAN

4-20

MPU

FAULT

TP1

TP11

TP9

TP5

TP8

TP10

198M1C

ISS M

ZERO

TP12

DISP

MPU active LED

(Flashing)

Fault LED

Sens V Test Point

TP7 + TP12

Sensor cell input

Sensor Volts

(RV3)

Zero

(RV2)

Span

(RV1)

4mA

(RV4)

Sensor Zeroing LEDs

CAN Transmitting LED

4-20mA SInk/Source

4-20mA Test

Jumper

End-of-line Jumper

Relay/Win Ribbon

LCD Contrast

Win Only

RS232

PC Data In/Out

Win Data Ribbon Cable

4-20op Test Points

FIELD TERMINALS

HI LO

24V Can+ Can- OV 4-20mA

24V Hi

Lo OV 4-20

Control Unit

CAN 1 or 2

Sensor

Addressable

+24
Hi
Lo
0v
4~20mA

+24

Control Unit

4~20mA Input

Sensor

3-Wire Direct

4~20mA Signal

+24
Hi
Lo
0v
4~20mA

+24

Sig

EOL

FAULT

MPU

204M1C

ISS M

CONTRAST

Fault LED

Gas Type Header

Sensor cell input

20mA

Span

(RV2)

4mA

Zero

(RV1)

Sensor 4-20mA Routing Configurations

(see diagram)

CAN Transmitting LED

4-20mA Test

Jumper

Relay/Win Ribbon

LCD Contrast

Win Only

End-of-line Jumper

+24V Test Point

(w.r.t 0V)

+24V

RS232

PC Data In/Out

Win Data Ribbon Cable

4-20mA Test Pins

4-20mA Sink Source

External 4-20mA Input

(eg. Infrared)

+24V O/Pt

(eg. Infrared)

FIELD TERMINALS

HI LO

24V Can+ Can- OV 4-20mA

24V Hi

Lo OV 4-20

Mainboad to Sensor wiring

Sensor Jumper configuration

Control Unit

CAN 1 or 2

Sensor

Addressable

+24
Hi
Lo
0v
4~20mA

4~20 IN

+24

Lo
0v

Control Unit

Addressable Sensor PCB

J10

+24V
Hi
Lo
0v
4~20mA

4~20mA O/P Sensor

4~20mA

+24V

4~20mA

+24V

Lo
0v

J11

Control Unit

4~20mA Input

Sensor

3-Wire Direct

4~20mA Signal

+24
Hi
Lo
0v
4~20mA

+24

Sig

Control Unit

4~20mA Input

Sensor

2-Wire Direct

4~20mA Signal

+24
Hi
Lo
0v
4~20mA

+24

Sig

4~20 IN

J10

Fig.3

Fig.4

Fig.5

The Combi sensors which have an LCD display fitted also
incorporate 3 reed switches which can be activated using
external magnets through the glass window of the flameproof
XDIwin enclosure.

These magnets do not act instantly and

have to be in close proximity to L, M and R on the front

display for a few seconds to activate a software setup

function.

The left magnet

enters the Auto zero ON or OFF menu.

This allows small drift changes in the sensor to be compensated
for but is not operational when the sensor readings are greater
than 5% of full scale. Therefore auto zero is inactive when a larger
gas reading is present. When the remove magnets message
appears, move the left magnet away and then the display shows
if auto zero is ON or OFF. The left magnet puts auto zero on
and the right magnet turns it off. With no magnets present, the
display will return to normal after a few seconds timeout.

The right magnet

allows the CAN address of the sensor to be

changed. WHEN the ADDRESS menu is displayed with a prompt
to remove the magnet, and then the display shows the address
and that the right magnet will decreases it whilst the left magnet
will increase it. This is then stored in internal non volatile memory
and the display will automatically revert to normal operation.

The centre magnet

is used to inhibit the sensor. As with the left

and right magnet functions the display requests that you remove
the magnet and then the state of the inhibit appears on the LCD.
The left magnet then puts the sensor into inhibit whilst the right
magnet removes it. An amber LED on the front panel under the
LCD flashes when the sensor is inhibited. When all magnets are
removed, the display will revert to normal operation.

The left and right magnets together allow the calibration

menu to be used.

Removing both magnets as instructed on the LCD presents the
first part of this multi menu which is ZERO. With no gas present
use the left magnet to increase the reading and the right magnet
to decrease to achieve a zero reading on the displays. A timer
is displayed on the LCD and when this reaches 0, the next
menu is displayed. This timer is 15 seconds approximately and
is reset back each time a magnet is near. Waiting till timeout
is acceptable but this timeout can be speeded up by placing a
magnet near to the centre position.

SPAN is the next part of the menu and gas should be applied to
the sensor at this time.

The left magnet increases the gain and the right magnet reduces
gain. The actual sensor value can be seen on the display to rise
or fall respectively.

LOW ALARM is the next menu and left and right magnets increase
and decrease this value.

HIGH ALARM is next followed by over range alarm.

The direction of the alarms is displayed as ^ for rising and v for
falling but these can be changed using left and right magnets
together.

Using magnets (set up)

Fig.1

204

Toxic

TP8

TP15

TP7

Display

Contrast