Elektrogas EVRM-NC User manual

elektrogas.com
EVRM-NC
EVRM-6NC
Safety solenoid valves for gas
Manual reset - Normally closed
DN10 … DN200
EE166 -0407

ELEKTROGAS – MANUALE TECNICO
2-12
EVRM-NC
EVRM-6NC
Safety solenoid valves for gas
Manual reset - Normally closed
Contents
Description ………………………………………….. 2
Features …………………………………………….. 2
Functioning and application ………………………. 3
Accessories and optionals ………………………… 4
Technical specifications …………………………… 4
Gas flow chart (pressure drop) …………………… 6
Ordering information ………………………………. 8
Standards and approvals …………………………. 9
Installation and servicing ………………………….. 10
Description The EVRM-NC /6NC type valve is a manual reset safety valve that is normally closed (open
when energized). The closing function is electrically activated. This type of device, connected to
one or more gas leakage detectors, safety thermostat or alarm signals for the presence of
carbon monoxide, is suitable to perform locking operations on the gas line.
Features The valves are made of aluminum alloy die-cast (or hot-pressed brass for OT versions), with a
wide range for inlet/outlet connections from DN10 up to DN 200.
Suitable for use with air and non-aggressive gases included in the 1, 2 and 3 families (EN 437).
This valve is open only when energized: if, for any reason, power supply goes down, the valve
closes immediately (intrinsic safe).
An incorporated fine mesh filter protects the valve seat and disc as well as downstream
components and prevents dirty contamination (except brass models).
Provided with G1/4 pressure gauge on two sides in the inlet chamber (except brass models).
Flanged models are provided with gauges in the outlet chamber too. Other gauge points on
request.
Provided with G1/8 connection on the bottom for closed position indicator micro switch from
DN65 to DN200 (on request from 3/4" to 2").
The coils are provided with ISO 4400 plug or with terminal box for DN100 and higher. Both
systems are provided with suitable cable gland to avoid water and dirty contamination.
Pipe connections meet group 2, according to EN161 requirements.
All components are designed to withstand any mechanical, chemical and thermal condition
occurring during typical service. Effective impregnation and surface treatments have been used
to improve mechanical sturdiness, sealing and resistance to corrosion of the components.
Valves are 100% tested by computerized testing machineries and are fully warranted.
WARNING
This control must be installed in compliance with the rules in force.

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Functioning and
application The EVRM-NC type valve is a manual reset safety valve that is normally closed. When not in
working position the spring works on the shutter keeping the gas orifice closed. Simply by
energizing the coil the valve does not open. It is necessary to manually move the reset rod
located at the top of the coil. Once opened, the valve can maintain this position until electric
current circulates on the coil. In absence of electric current the valve closes rapidly and remains
shut upon return of same. Once the causes for the lock have been eliminated, valve must be
opened manually as described above.
Fig.1
The /6NC versions are provided with a dual-shutter system for pressure compensation. To open
the valve pull the knob for the first step, wait for pressure compensation, and then pull the knob
completely up to full resetting (from 3/4" to 6”).
This kind of device is normally installed downstream a manual shut-off valve and upstream of
the gas regulating train. Figure 2 shows a example of installation.
Fig.2
WARNING
Location and mode of installation must be in compliance with local rules in force.
Gas
detector
Solenoid valve
manual reset
Gas
network
Consumer

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4-12
Accessories and
optionals A fine mesh filter is provided, to prevent dirty contamination of the seal seat. However, an
external strainer must be installed upstream of the valve. Brass models are available without
internal filter only.
Inlet pressure chamber is provided with bilateral G1/4 gauges, to connect manometers,
pressure switches, leakage tester or other gas equipments. Flanged models are provided with
gauges in the outlet chamber too. Brass models are available without gauges only.
Models from DN65 to DN200 are provided with G1/8 connection on the bottom for closed
position indicator micro-switch (on request from 3/4" to 2"). To install the micro-switch the
installing kit must be required.
The threaded models Rp11/2 and Rp2 can be provided with flanged connections using an
optional kit.
All the valves may be provided with Ex-proof marking in accordance with the 94/9/EC Directive,
for use in Zone 2.
Technical
specifications Tab. 1
Connections Gas threaded ISO 7/1 from Rp3/8 to Rp2
Flanged PN16 – ISO 7005 from DN40 to DN200
Voltage rating 230 VAC 50/60 Hz
110 VAC 50/60 Hz
24 VAC/DC
12 VAC/DC
Voltage tolerance -15% / +10%
Power consumption see charts
Ambient temperature -15°C / +60°C
Max. operating pressure 600 mbar (60 kPa)
6 bar (600 kPa)
Flow capacity see charts
Closing time < 1 second
Filter (except brass models) 600 µm, metal mesh
Protection class IP65 (EN 60529)
Cable gland PG 9
Coil winding insulation Class H (200°C)
Coil thermal resistance Class F (155°C)
Materials in contact with gas Aluminium alloy
Brass
Stainless steel
Plated steel
Anaerobic adhesive
Nitrile rubber (NBR)

ELEKTROGAS – MANUALE TECNICO
5-12
Fig.3
Tab. 2
Material and
connections
Overall dimensions
[mm]
CuZn AlSi
Power
consumption
@230VAC
[W]
Flow factor
Kvs
[m³/h] A B C D Int h
Peso
[Kg]
Rp 3/8 8 0,7 30 58 115 130 - - 0,4
Rp 1/2 8 1,0 30 58 115 130 - - 0,4
G 3/4 8 2,0 35 55 113 130 - - 0,6
G 1 8 4,5 40 62 115 137 - - 0,7
Rp 3/8 12 2,9
70 77 148 164 - - 0,9
Rp 1/2 12 4,0
70 77 148 164 - - 0,9
Rp 3/4 12 9,5
85 96 158 180 - - 1,1
Rp 1 12 12,0
85 96 158 180 - - 1,1
Rp 11/4 12 20,0
120 153 188 220 - - 2
Rp 11/2 12 26,0 120 153 188 220 - - 2
Rp 2 12 40,0
106 156 192 230 - - 2,3
DN 40 (1) 12 26,0 150 193 188 262 110 4x18 3,7
DN 50 (1) 12 40,0 165 196 192 274 125 4x18 4,3
DN 65 25 63,0
200 305 262 (2) 352 (2) 145 4x18 7,6
DN 80 25 80,0
200 305 262 (2) 352 (2) 160 8x18 7,6
DN 100 45 148,0
252 350 305 (2) 435 (2) 180 8x18 17
DN 125 45 250,0
310 460 370 (2) 540 (2) 210 8x18 29
DN 150 45 315,0
310 460 370 (2) 540 (2) 240 8x23 31
DN 200 45 516,0
370 546 425 (2) 635 (2) 295 12x23 46
(1) Optional Kit (2) Valve open

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dP [mmH O]
1
2
2 3
10
5 4 6 8 7
20 30 80 70
100
50 40 60
200 300 800 700
1000 2000
5000
V [Nm³/h]
Rp 1½
G 3/4-OT
Rp 3/8-OT
Rp 1/2-OT
G 1-OT Rp 1/2
Rp 3/8
Rp 3/4
Rp 1¼
Rp 2
Rp 1
DN 200
0.2
0.4
0.3
0.8
0.7
0.5
0.6
6
2
3
4
5
10
7
8
20
30
40
80
70
50
60
100
300
200
600
400
500
1000
800
700
2000
3000
1
0.1
0.1
0.7
0.6
0.5
1
1
DN 125
DN 80
DN 65
DN 100
DN 150
100
80
810
10
3
2
2
3
5
4
7
6
6
5
4
8
7
2
4
3
7
6
5
8
70
80
60
40
50
30
20
30
10
20
20
40
30
60
50
50
40
70
60
800
600
500
400
700
300
200
100
70
80 100
200
300
200
500
400
400
300
600
500
4000
5000
3000
2000
1000
600
700
800
1000
700
800
1000
2000
3000
4000
3000
2000
4000
5000
1
dP [mbar]
0.1 0.2 0.3 0.7 0.8 0.5 0.4 0.6
1 2 3
10
5 4 6 7 8
30 20 70 80
100
50 40 60
0.2
200
0.7
0.8
0.6
0.4
0.5
0.3
0.2
0.3
0.2
0.4
0.3
0.6
0.5
0.4
0.7
0.8
0.8
Natural gas Air LPG Town gas
AIRGAS VkV ⋅=
Gas flow chart
(Pressure drop)
Formula of conversion
from air to other gases Tab. 3
15°C, 1013 mbar, dry
Gas type Specific gravity
ρ
[Kg/m³] GAS
.
k
ρ
251
=
Air 1,25 1,00
Natural gas 0,80 1,25
Town gas 0,57 1,48
LPG 2,08 0,77

ELEKTROGAS – MANUALE TECNICO
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When the flow read on the diagram is referred to operating pressure instead of standard
conditions, the pressure drop ∆p read on the diagram must be multiplied for the factor:
(1+ relative pressure in bar)
Example:
In the 2” solenoid valve with an air flow of 80 Nm3/h there is a pressure drop ∆p = 5 mbar.
If we consider that 80 m3/h is the flow at 200 mbar of inlet pressure, then the pressure drop to
be consider is:
∆p = 5x(1+0,2) = 6 mbar
Normally, pressure drop and flow rate for the valves are read from the gas flow diagram.
However, the valves can also be chosen in accordance with the characteristic ”Kvs value” which
is shown in table 2.
The selection of the valve requires the calculation of the Kv under the operating conditions.
Considering only subcritical pressure drops:
2
1
p
p<∆
Kv can be calculated with the formula:
()
2
273
514 pp
tV
Kv ⋅∆
+
=
ρ
where
V = flow rate [Nm3/h]
Kv = flow factor [m3/h]
ρ= density [Kg/m3]
p1= absolute inlet pressure [bar]
p2= absolute outlet pressure [bar]
∆p = differential pressure p1-p2[bar]
t = media temperature [°C]
To the Kv value calculated from operating conditions we add an allowance of 20%, to obtain the
minimum Kvs value which the valve should have:
Kvs > 1,2 Kv
Valve must be selected considering the following:
- Pressure drops ∆p ≤0,1p1are recommended and ∆p > p1/2 are always unadvisable
- Flow velocities w ≤15 m/s are recommended and w > 50 m/s are always unadvisable.

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Ordering
information
Tab.4
Additional code for special voltages
Designation (230V) 24 V 12 V
600 mbar 6 bar Connections 110 VAC AC DC AC DC
EVRMNC0O EVRM6NC0O Rp 3/8 brass
EVRMNC1O EVRM6NC1O Rp 1/2 brass
EVRMNC2O EVRM6NC2O G 3/4 brass
EVRMNC3O EVRM6NC3O G 1 brass
_ E G F H
EVRMNC0A EVRM6NC0A Rp 3/8
EVRMNC1A EVRM6NC1A Rp 1/2
EVRMNC2A EVRM6NC2A Rp 3/4
EVRMNC3A EVRM6NC3A Rp 1
EVRMNC35A EVRM6NC35A Rp 1¼
EVRMNC4A EVRM6NC4A Rp 1½
EVRMNC6A EVRM6NC6A Rp 2
EVRMNC4AF EVRM6NC4AF DN 40 (1)
EVRMNC6AF EVRM6NC6AF DN 50 (1)
EVRMNC7A EVRM6NC7A DN 65
EVRMNC8A EVRM6NC8A DN 80
EVRMNC9 EVRM6NC9 DN 100
EVRMNC93 EVRM6NC93 DN 125
EVRMNC95 EVRM6NC95 DN 150
EVRMNC98 - DN 200
B C D
NOTE: models up to DN80 are provided with DIN plug
(1) Optional kit
The versions with inlet pressure p1≤6 bar (600 kPa) may be order inserting the digit “6” in to
the designation.
Different voltage than 230V may be order adding to the standard designation the additional
code shown above.
Example:
EVRM6NC3A.B for a valve with Rp1 connections, 110VAC, 6 bar
Manufacturer reserves the right to update or make technical changes without prior notice.

ELEKTROGAS – MANUALE TECNICO
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Standards and
approvals The valve design meets current European approval requirements regarding safety shut-off
functions on gaseous fuels.
These products conform with the Pressure Equipment Directive (97/23/EC) and the certification
has been issued by the notified body:
C.S.I. Spa
Viale Lombardia 20
I-20021 Bollate (MI)
The following standards/technical specifications have been fulfilled:
- Electromagnetic Compatibility (89/336/EC)
- Low Voltage Directive (73/23/EC)
Quality Management System is certified according to UNI EN ISO 9001 and the monitoring is
carried out by the notified body:
Kiwa Gastec Italia Spa.
Via Treviso, 32/34
I- 31020 San Vendemiano (TV)

ELEKTROGAS – MANUALE TECNICO
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Installation and
servicing To assure a proper and safe operation, as well as a long life of the valve, the installation
procedure and a periodical servicing are very important topics and the following instructions
should be always fulfilled.
IMPORTANT: before proceeding with the installation, ensure that all the features of your system
are comply with the specifications of the valve (gas type, operating pressure, flow rate, ambient
temperature, electrical voltage, etc.).
CAUTION
Shut off the gas supply at the main manual shut-off valve and disconnect electrical
power to the valve before proceeding installation or servicing.
PIPING CONNECTION
- Check correspondence of flow direction with arrow printed on valve body.
- Check correct alignment of connecting pipes.
- Ensure that installing area is protected from rain and water splashes or drops.
- Remove the end caps and make sure no foreign body is entered into the valve during
handling.
THREADED MODELS
- Put sealing agent onto the pipe thread. Avoid excessive quantities which could enter in the
valve and damage the seal seat.
- Screw the pipes using proper tools only. Do not use unit as lever because damage to the
valve stem could result.
FLANGED MODELS
- Position the gasket or sealing agent on the flanges and insert the bolts with washers.
- Screw the nuts tightening them crosswise and using proper tools only. Avoid overtightening
and mount tension free.
Following chart shows the maximum values of bending moment (Fmax), torque (Tmax) and
screws driving torque (Cmax), according to EN161.
Tab. 5
Fig. 4
Valve may be mounted with coil in horizontal or vertical position. Coil may be oriented 360
degrees in any direction.
Connections Fmax
(Nm) t<10 s
Tmax
(Nm)
Cmax
(Nm)
Rp3/8 70 35 -
Rp1/2 105 50 -
Rp3/4 225 85 -
Rp1 340 125 -
Rp1¼ 475 160 -
Rp1½ DN40 610 200 50
Rp2 DN50 1100 250 50
DN65 1600 - 50
DN80 2400 - 50
DN100 5000 - 80
DN125 6000 - 160
DN150 7600 - 160
DN200 7600 - 160
Maximum 90°
from vertical