Differential pressure is a type of flow switch in many industrial applications. Differential pressure type flow switches determine the value of flow protection according to the pressure difference corresponding to the minimum flow allowed for normal operation of a variable flow of a pump. Once the operating flow is below the minimum, Allowed flow is protection, to ensure that the heat exchanger will not be frozen.
Here is the installation of the differential pressure water flow switch on the primary pump transformer system:
1. The differential pressure type water flow switch installed in the primary pump transformer system must be welded with a pressure measurement interface at the water inlet and outlet of the heat exchanger;
2, the inlet pipe is connected to the "+" end, and the outlet pipe is connected to the "-" end;
3, the pressure measuring tube and the casing of the pressure difference type water flow switch need to be insulated;
4. The product provides SPDT contacts, that is, a normally open and a normally closed contact are available for access to the controller. The factory defaults to the normally open contact;
5. Differential pressure water flow switch can be installed directly by the factory, and the line is directly connected to the controller of the chiller unit, reducing the possibility of installation errors by the on-site personnel. This will undoubtedly increase the cost of the manufacturing plant, but can significantly reduce Technical consultation and maintenance costs incurred by switching;
6. At the same time, it can also be provided to the field installer as an accessory, and the installation can be performed on site according to the situation. Users can weld a G1 / 2 ”inner wire on the water inlet and outlet pipes on the site, install a small ball valve, and then install a G1 / 2” -1/4 ”SAE (7/16” -20UNF) joint, through the 6.35 copper pipe The enlarged bell mouth is connected to a pressure difference type water flow switch, but the pressure difference type water flow switch needs a fixed bracket;
In addition, you can also choose G1 / 4 ”for the“ + ”side of the differential pressure switch and 1/4” SAE (7/16 ”-20UNF) for the“-”side. After passing the G1 / 2 ”to G1 / 4” external thread conversion head, connect the G1 / 4 ”internal thread ball valve, and then screw the water flow switch directly to the valve. The other end is connected in the same way as the previous method. This connection method has a fool-proof effect, and the user's on-site installation will not mistake the "+" and "-" ends;
7. The advantages of on-site installation can flexibly choose the installation location according to the site conditions.