9
■
EPDT-247i
■
5.2 Nominal size selection
Cv value calculation formula
<Steam>
When
2
P
P
1
2
>
)
P
P
(
P
138
Wk
Cv
2
1
+
∆
=
When
2
P
P
1
2
≤
1
P
120
Wk
Cv
=
<Air>
When
2
P
P
1
2
>
)
P
P
(
P
G
)
t
273
(
2940
Q
Cv
2
1
+
∆
+
=
When
2
P
P
1
2
≤
1
P
2550
G
)
t
273
(
Q
Cv
+
=
<Liquid>
P
G
V
365
.
0
Cv
∆
=
Cv: Cv value of each nominal size
∆
P: P
1
– P
2
[MPa]
W: Max. steam flow rate [kg/h]
K: 1 + 0.0013 × {superheated steam temp.[˚C]
Q: Max. gas flow rate [m
3
/h (standard condition)]
– saturated steam temp. [˚C]}
V: Max. liquid flow rate [m
3
/h]
G: Specific gravity (relative to air for gas,
P
1
: Inlet pressure [MPa
·
A]
or relative to water for liquid)
P
2
: Outlet pressure [MPa
·
A]
Cv value
Nominal size
10A
15A
20A
25A
32A
40A
50A
65A
DP-100, DP-100F,
DP-100-D, DP-100F-D,
DP-100-C, DP-100F-C
3.0
4.5
7.5
12.0
17.7
25.0
33.6
33.6
6. Installation
Warning
Electric wiring work must be done by experienced professional.
1. If there is a risk of death, bodily injury or damage to property at the time of malfunction of the product,
be sure to install a suitable safety device that controls fluid flow interception/release or sounds an
alarm.
2. The product cannot be used as an emergency shutoff valve.
* The product is not designed as a safety valve such as an emergency shutoff valve. If the product
is applied to a system that needs safety measures, install other equipment besides the product to
ensure the safety.
3. The product is not explosion-proof. Do not use it in the area or ambience where explosive gases
accumulate.
* Using the product under the said conditions may cause fire.
4. Connect the cables only after confirming that no power is supplied.
* Failure to follow this notice may cause an electric shock.
5. Connect the cables according to the instructions after confirming the rated voltage.
* Erroneous cable connection may cause an electric shock or fire.
6. Do not supply electric power to the coil while it is detached from the valve.
* Failure to follow this notice may result in coil burnout or fire due to an overcurrent.
