The end test valve consists of two ball valves and a sight window, with the valve body made of brass. The inlet is an internal threaded connection, and the outlet is an external threaded connection. The ball valve on the inlet side is a two-position "on/off" type, with a flow direction indicator on the valve body. The middle ball valve is a two-position "on/test" type. When both valves are in the "on" position, it functions as a DN25 (or DN32, or DN50) ball valve. When set to the "test" position, it corresponds to the flow coefficient of a DN15 sprinkler. During design selection, a pressure gauge should be installed on the inlet side.

I. Purpose of the End Test Device with Sight Window:

According to the requirements of Clause 6.5 in the National Standard GB50084-2001 "Design Code for Automatic Sprinkler Systems": "At the most hydraulically remote sprinkler controlled by each alarm valve group, an end test device shall be installed. At the most hydraulically remote sprinkler in other fire compartments and floors, a test valve with a diameter of 25mm shall be installed." In response to this requirement, our company has redesigned and developed two types: all-copper and copper-steel mixed, the ZSPM-series end test devices, providing convenience for the design, installation, debugging, inspection, acceptance, and use of modern fire protection engineering.

II. Features of the End Test Device with Sight Window:

This device mainly consists of a solenoid valve (or manual ball valve), pressure gauge, standard nozzle, and specially designed pipe section. The automatic control type can also be equipped with a signal feedback pressure switch. When the fire control center supplies DC24V voltage to the end test device, the solenoid valve opens, and the end test device starts spraying water. Meanwhile, the pressure switch feeds the working signal back to the fire control center. The standard nozzle operates at a pressure of 0.1MPa and a flow rate of 80L/min. The flow coefficient K=80 can simulate the action of a system sprinkler for testing the system. If the system pressure is 0.1MPa during testing, the flow rate at this pressure can be obtained by referring to the flow-pressure characteristic curve of the standard nozzle. Therefore, this device also has the function of detecting pressure and flow, facilitating regular testing of the reliability of water flow indicators and wet alarm valves.

The end test devices produced by our company can be installed horizontally or vertically in locations convenient for operation and observation. (To read the pressure gauge, simply adjust the orientation of the gauge surface.)

III. Types of End Test Devices with Sight Window:

1. The ZSPM-series end test devices are divided into ZSPM—Type I (manual control) and ZSPM—Type II (solenoid valve control) based on engineering design requirements. Based on manufacturing materials, they are classified into high-grade (all-copper) and standard (copper-steel mixed) types.

2. The ZSPM end test devices produced by our company are of the static and dynamic pressure display type.

3. Upon user request, dynamic pressure type or end test devices with pressure switch feedback signals can be custom-made.

IV. Main Technical Parameters of the End Test Device with Sight Window:

1. Inlet thread: R1 (internal)??????6. Solenoid valve voltage: DC24V, current: 0.8A

2. Outlet thread: R3/4 (external)????7. Flow characteristic curve, flow coefficient K=80

3. Nominal diameter DN=25???????8. Pressure gauge (Y-40) axial 0-1.6MPa (2.5 grade).

4. Rated working pressure: 1.2MPa???9. ZSPM-I type (length x width): 170x50

5. Seal test pressure: 2.4MPa??????ZSPM-II type (length x width): 240x90

V. Other Notes for the End Test Device with Sight Window:

1. An end test device should be installed at the most hydraulically remote point of each alarm valve's water supply.

2. The end test device can be installed vertically or horizontally at the end of the pipeline network for easy operation.

3. According to the newly added clause, the discharge method of the end test device's outlet water should adopt orifice outflow into the drainage pipeline.

4. Inlet connection: R1 (internal).

5. Outlet thread: R3/4 (external).