I have a question: how many wires are needed to connect the cable of an electric contact pressure gauge?
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It uses 2X2X1. For 5, it’s still two 1X2X1s. Oh, 5. Is there anyone who’s an expert and can explain this to me? When should a four-wire instrument use one cable and when should it use two cables?
Electrical contact pressure gauge: It has three wires connected to it – one wire is used in common to move the pointer, while the other two wires are connected to the high and low pressure levels respectively.
2X2X1. 5 or 3*1 will work; it’s best to have one with shielding
The electric contact pressure gauge uses a three-core cable, 3×1.5, with one core serving as the common wire
Use a three-core cable: 3×1.5 will suffice. The wiring for electric contact pressure gauges is completely different from that of four-wire instruments!
It depends on whether you use high or low trigger levels; if both are needed, a 3-core cable should be used
Under normal circumstances, the signal from a pressure gauge with electrical contacts is of the SPDT type, that is, it features single-pole double-throw contacts: one common terminal, one normally open contact, and one normally closed contact. A 3*1.5 mm² shielded control cable is sufficient; of course, a 2*2*1.5 mm² cable can also be used, but care must be taken to avoid any problems that may arise during installation. In other words, the size of the inlet for the instrument must match the outer diameter of the cable; if the cable’s diameter is incorrect, wiring cannot be completed. Also, regarding the issue with four-wire meters. As a general principle, the power supply circuit and the signal circuit are designed to be separate; that is, 2*2.5+T cables are used for power supply, while 1*2*1.5 cables are used for the signal circuit. If a single cable is used to provide both power and signals, it is important to ensure that the voltage level for power supply is the same as that of the signal circuit. For example, if the instrument is powered by a 24V supply and the signal circuit also operates at 24V, then it is possible to use the same cable. Although this meets the mandatory requirements for electrical wiring, it is very rare to hear of anyone doing this in the chemical instrumentation industry. However, some instrument manufacturers offer four-wire instruments with only one wiring terminal, which means that it is necessary to use a single cable to connect both the power and signal circuits. 1# purelove310
7# davidgrommet said it very clearly; grab it quickly!
For electrical contacts, a three-core wire is used; 3*1.5 is sufficient
KVVP 3*1.5 is a 3-core, 1.5-diameter cable with double shielding; it is a solid wire.
It is recommended that you use 3*1.5, as this allows for some margin and can also be used for grounding