Pulse Output - YOKOGAWA DY025 User Manual

Table 3.1 The connection example for simultaneous analog and pulse and alarm, status output.
Connection
Analog Output
digitalYEWFLO Electrical Terminal
In this case,
Communication is
possible (up to a distance
of 2km when a CEV cable
is used.)

Pulse Output

digitalYEWFLO Electrical Terminal
In this case,
No communication is
possible.
digitalYEWFLO Electrical Terminal
Status Output
Alarm Output
In this case,
No communication is
possible.
When analog and pulse output are used, the length of communication line is subjected to wiring conditions. Refer to
example 1 to 3. If the communication carries out from amplifier, no need to consider wiring conditions.
Simultaneous
Analog
-Pulse Output
Example 1
In this case, Communica
-tion is possible(up to a
distance of 2km when a
CEV cable is used).
digitalYEWFLO Electrical Terminal
Example 2
In this case, Communica
-tion is possible (up to a
distance of 200m when a
CEV cable is used) and R
Ω
= 1k ).
digitalYEWFLO Electrical Terminal
Example 3
In this case, No communi
-cation is possible (when
shielded cable is not used).
digitalYEWFLO Electrical Terminal
The range of load
resistance R for
the pulse output.
*1 : To avoid the influence of external noise, use an electric counter which fits to the pulse frequency.
*2 : Resistor is not necessary in case of an electric counter which can receive contact pulse signal directly.
+
SUPPLY
–
+
PULSE
Shielded Cable
+
SUPPLY
–
+
PULSE
Shielded Cable
+
SUPPLY
–
+
PULSE
Shield
Shielded Cable
+
SUPPLY
–
Outer Jacket
+
PULSE
Shield
Shielded Cable
+
SUPPLY
–
Outer Jacket
+
PULSE
+
SUPPLY
–
+
PULSE
The load resistance should be selected by calculation as shown below.
E (V)
Ω
R (k )
µ
120 C (
2
E (V)
P (mW) =
Ω
R (k )
Description
Distributor
+
24V DC
250Ω
–
*2 R
Electric counter
External Power supply
30V DC, 120mA max
(Contact Rating)
Distributor (or communication medium)
*2
(R)
Electric counter *1 (or communication medium)
Ω
250
Ω
250
*2
(R)
0.1
Example of CEV cable capacitance
F ) × f ( kHz )
0.1µF/km
6
Where
E = Supply voltage (V)
f = Frequency of pulse output (kHz)
R = Value of load resistance (k
3-3
Use the Three-wire shielded cable.
This supply voltage requires a power
E
sourse with a maximum output
current of no less than E/R.
*1
Use the Three-wire shielded cable.
E
Relay
AC power supply
For the shielded cables in this
example of flowmeter installation,
24V DC
use two-wire separately
shielded cables.
250Ω
This supply voltage requires a
E(10.5 to 30V DC)
power sourse with a maximum
Counting input
output current of no less than
E/R.
Common
For the shielded cables in this
Recorder or
example of flowmeter installation,
other instrument
use two-wire separately shielded
cables.
This supply voltage requires a
E(16.4 to 30V DC)
power sourse with a maximum
*2
(R)
output current of no less than
Counting input
E/R+25mA.
The supply voltage requires output
Common
impedance no more than 1/1000 of
R (load resistance).
Electric counter
*1 (or communication medium)
Recorder or
other instrument
This supply voltage requires
E(16.4 to 30V DC)
a power sourse with a
Counting input maximum output current of
no less than E/R+25mA.
Common
Electric counter
*1 (or communication medium)
C = Cable capacitance (µF)
P = Power ratio of the load resistance
Ω
) (mW)
3. WIRING
Mognetic
valve
T030301.EPS
IM 01F06A00-01E