--<< GD2A = 01 >>-20150319

specification document
Remote measurement 2-wire transmitter unit
Model：ＧＤ２Ａ

Azbil Kimmon Co., Ltd.

--<< GD2A = 02 >>--Overview
This transmitter is a 2-wire no-voltage contact transmitter required to connect a water meterto an electronic counter (KDC-811), a centralized meter reading board for pulses, or a computer.

Structure
GD2A has a built-in reed switch, the shape of which is shown in a separate figure.

Technical specification・Transmitter

Contact capacity

２.５ＶＡ

Max. contact
voltageMax. contact
current
Contact withstandvoltageBounce time

ＤＣ５０Ｖ
ＤＣ１００ｍＡ
DC250V for 1 minute
10msec or lessAmbient operating
Below 55℃ ※temperature※ Complies with JIS B 8570-2 “Water meters and hot water meters”
・Vinyl Cabtire Tire Cord (VCTF)

Wire Core Thickness ０．５ｍｍ２
Wire Number

２

Wire Color

Black and white

Length１．５ｍ

Standard Terminal
Processing

With fork terminal for M3 screwor１０ｍ

--<< GD2A = 03 >>--Operation
The GD2A (2-wire transmitter) reed switch is operated by a magnet built into the water
meter as shown in the figure below.

Water flow

WhtWhtWhtWhtBlkBlk

Blk

Transmitter
Blk
ONONOFFOFF

Meter outgoing pulse(e.g.) For water meter GKDA13, 1m3/ Ｐ

Attention
１）Pulse width (time it is ON) varies depending on the flow rate.
２）If the water meter stops when the reed switch is in the ON state, the reedswitch will remain in the ON state as long as there is no water flow.
Similarly, if the water meter stops when the reed switch is in the OFF state,
the reed switch will remain in the OFF state as long as there is no waterflow.
３ ） Using the GT-ER2 pulse relay (manufactured by us), the meter's outgoing
pulse can be output as a stable one-shot (approx. 0.1 second) no-voltage
contact. It is recommended to use the GT-ER2 when inputting to computers,
data loggers, etc. (For details, refer to the GT-ER2. (For details, refer tothe specifications of GT-ER2.) Also, when inputting directly to a computer,data logger, or other device, make sure that the input specifications of thecomputer or other device match the specifications of the above-mentioned
transmitter unit.

--<< GD2A = 04 >>--

Meter type and outgoing pulse・Refer to the specifications of the meter to be used for the type of meter and the pulse unit tobe transmitted.

Precautions for use
１）The reed switch incorporated inside is made of a very thin glass tube, so it should
be handled with special care and not subjected to shocks, etc.
２）The terminal connections should be waterproof.
３）Avoid storing power cables in or near other cables (power lines) in the same conduit,
as this may cause malfunctions.。
４）If there is a possibility of inductive interference, use a shielded wire, etc. toprevent interference. (The shield should be grounded at the receiving end.)５）If there is a possibility that the back EMF generated by the operation of thereceiving side may exceed the rated voltage, be sure to insert a prevention circuit.
(This is not necessary when using our receiver.)６）If the meter is installed outdoors, it should be protected from direct sunlight by asunshade or racking, as is the case with the water meter itself.
７）Install in a location where there is no danger of freezing. In winter, consider heatinsulation to prevent the meter and transmitter from freezing (freezing with rainwater,etc. on the transmitter may cause malfunction). (If the transmitter freezes withrainwater, etc. adhering to it, it may malfunction.)--<< GD2A = 05 >>--

Pulse width at maximum flowrate (ON time)

water meter

TypeMeter Type

Pulse unit

ON timeGKDA(L)131ｍ３／Pulse

115 seconds or more

GKDA201ｍ３／Pulse

72 seconds or more

GKDA(L)25

1ｍ３／Pulse

45 seconds or more

GKDA30,40

1ｍ３／Pulse

28 seconds or more

GKDS40,50

1ｍ３／Pulse

18 seconds or more

GFDW(T)50

1ｍ３／Pulse

7 seconds or more

GFDW(T)65,75

1ｍ３／Pulse

4 seconds or more

３／Pulse2 seconds or more

GFDW(T)100

1ｍAttention
・Since the ON time varies depending on the flow velocity, the ON time shown here is
the ON time when the maximum instantaneous flow rate (Q4) is applied. Normally, theON time will be longer than this.
※ ON and OFF times are determined by flow velocity and transmitter duty ratio.
※ The duty ratio may vary slightly depending on the individual reed switch.

1234AA

Fork terminal for M3
screw

2-wire cableφ5B13.5BC

D

D

20C

42E

FE

3.

.

2
1.
.

.
.

記号箇所年 月 日 変 更 記 事 法
承 荻生 検製
図

認

1大塚

図

高野2012/09/06

材
質
投影尺 度

備
考

GD2A
2線式パルス発信器

名称発信器

図

アズビル金門株式会社 番F

Y-GD2A-A110B-000A00

4