NDR 320

Container systems according to A3 B3/4 and container systems according to A4 B3/4

The low pressure regulator 320 is a 2nd stage pressure regulator for LPG, which reduces the regulated pressure from the 1st stage pressure regulator to a nominal 50 mbar. A safety shut-off valve (OPSO) is mounted on the regulator and a safety relief valve (PRV) is integrated as safety-related equipment.

Indoor system “t” – Model 4b DIN 4811 This low-pressure regulator meets the requirements of model 4b “t” if a thermally triggered shut-off element (fuse) is connected upstream.
In this case of application – indoor unit “t” – a blow-off line must be led from the ventilation opening of the low-pressure regulator 320 to the outside.

PN 4 low pressure regulator – “f” – 24 kg/h
DVGW approved: According to EN 16129/ CE approved according to 2016/426/EG

TECHNICAL DATA
  • DVGW approved: According to EN 16129/ CE approved according to 2016/426/EG
  • Inlet pressure: 0.5-4 bar
  • Inlet connection: G 1/2 “IG or others on request
  • Outlet connection: G1/2 “IG or others on request
  • Capacity: 24 kg/h (propane)
  • Outlet pressure: 50 mbar or other on request
  • Overpressure safety shut-off valve (OPSO): 95-132 mbar
  • Overpressure safety relief valve (PRV): 135-150 mbar
  • Weight: 2 kg
  • Gas: LPG/LNG/Propane/Butane/Natural gas or others on request
  • Operating temperature: -40°C to +80°C
OPERATING PRINCIPLES

The low-pressure regulator reduces the regulated pressure from the 1st stage pressure regulator in a single stage to a nominal 50 mbar. In the event of an impermissibly high increase in the outlet pressure of the regulator, the response pressure of the safety shut-off valve (OPSO) is reached, which then closes automatically and shuts off the gas flow upstream of the regulator. The respective operating status of the OPSO can be seen on the visual display.

Clear = open
Red = closed

If there is a further increase in pressure, e.g. due to the OPSO not closing completely, the safety relief valve (PRV) automatically releases a limited amount of the gas flow into the atmosphere after the set response pressure has been reached.

PRODUCT TYPES
Low pressure regulator NDR-320 Output pressure Performance Order number
NDR-320-G 1/2 IG x G 1/2 IG 50 mbar 24 kg/h 1 00 320 8 5 000 0
NDR-320-LVS15 x LVS15 50 mbar 24 kg/h 1 00 320 8 5 115 0
NDR-320-LVS18 x LVS18 50 mbar 24 kg/h 1 00 320 8 5 118 0
NDR-320-LVS22 x LVS22 50 mbar 24 kg/h 1 00 320 8 5 122 0
NDR-320-RVS15 x RVS15 50 mbar 24 kg/h 1 00 320 8 5 215 0
NDR-320-RVS18 x RVS18 50 mbar 24 kg/h 1 00 320 8 5 218 0
NDR-320-RVS22 x RVS22 50 mbar 24 kg/h 1 00 320 8 5 222 0
NDR-320-PVS15 x PVS15 50 mbar 24 kg/h 1 00 220 8 5 515 0
NDR-320-PVS18 x PVS18 50 mbar 24 kg/h 1 00 320 8 5 518 0
NDR-320-PVS22 x PVS22 50 mbar 24 kg/h 1 00 320 8 5 522 0
INSTALLATION AND OPERATING INSTRUCTIONS

PN 4 low pressure regulator – “f” – 24 kg/h
DVGW approved: According to EN 16129/ CE approved according to 2016/426/EG

TYPE NDR-320 with OPSO and PRV

DESCRIPTION
The pressure regulator type 320 is a pressure regulator of the 2nd stage, which transfers the regulated pressure from the pressure regulator of the 1st stage to a fixed outlet pressure. The following safety equipment is fitted to the regulator: safety shut-off valve (OPSO) is mounted on the regulator and a safety relief valve (PRV) is integrated in the low-pressure regulator.

A. INDIVIDUAL DESCRIPTIONS
1. Safety shut-off valve (OPSO)
The OPSO is open during normal operation and has the function of automatically shutting off the gas flow as soon as the set response pressure is reached. It must be opened manually after closing.

2. Pressure regulator
The pressure regulator reduces the regulated pressure from the 1st stage pressure regulator to a fixed set outlet pressure.

3. Safety relief valve (SRV)
The SRV is closed during normal operation and has the task of automatically releasing the gas flow as soon as the pressure in the system to be protected exceeds the response pressure. It closes again automatically when the pressure drops below the set pressure.

B. MODE OF OPERATION
The pressure regulator reduces the regulated pressure from the 1st stage pressure regulator to a nominal 50 mbar.
If the outlet pressure at the regulator rises inadmissibly high, the response pressure of the safety shut-off valve (OPSO) is reached, which then closes automatically and shuts off the gas flow upstream of the pressure regulator. The respective operating status of the OPSO can be seen on the visual display.

Clear = open
Red = closed

If there is a further increase in pressure, e.g. due to the OPSO not closing completely, the safety relief valve (PRV) will automatically release a limited amount of the gas flow into the atmosphere after the set response pressure has been reached.

ATTENTION ! All activities described in points C, D and E may only be carried out by authorised specialist personnel.

C. ASSEMBLY
1. Outdoor installation “f”
In this case, the pressure regulator is installed on the building in front of the house inlet in a house connection box.

2. Indoor installation “t”
If the pressure regulator is installed inside the building, a thermally triggered shut-off device (fuse) must be connected upstream of it. 
It is essential to ensure that a blow-off line is led from the PRV to the outside. The ventilation opening or blow-off line must always be
must always be open, otherwise the OPSO will lock due to pressure increase.

IMPORTANT ! – Only use proper tools for assembly. – Prevent sealants from getting into the gas-carrying components. – Always counteract threaded connections with suitable keys. – After assembly, a careful leak test must be carried out.

D. START-UP
Start-up is carried out by slowly opening the extraction valve on the liquid gas container.
If the OPSO has locked, the following steps are required:

– Close the extraction valve on the liquid gas container
– Relieve the pressure at the pressure regulator (inlet and outlet).
– Twist off the plastic cap of the OPSO
– Pull out the OPSO plunger until it engages.
– Screw the plastic cap back on
– Slowly open the extraction valve on the liquid gas container.

E. FUNCTION TEST OF THE PRESSURE REGULATOR
– Check the inlet pressure: test connection G1/4 no. 8
– Checking the outlet pressure: test port G1/8 no. 3
– Set pressure and function test of OPSO/PRV: test port G1/8 no. 3.

During the test, the gas supply must be interrupted and the consumer unit closed. A safe and quick function test can be carried out with the “Müller test device”. A leak test must be carried out after each test.