APPLICATION

GENERAL DESCRIPTION & OPERATION

The glass-filled polycarbonate housing contains a sensing diaphragm and includes an integral snap-acting switch. Sample line connectors are located on either or both sides of the diaphragm to accept air sample connections. The electrical connection consists of male 90° quick-connect terminals.The snap action switch can be actuated by a pressure or vacuum air flow, or by a pressure or vacuum differential.

MOUNTING

Various mounting brackets are available. Figure 1 shows two typical styles. Select a mounting location free from vibration. Mount with the diaphragm vertical, or at a custom angle. Specify the mounting position when ordering. Avoid mounting with the sample line connections directed upward.

ELECTRICAL CONNECTIONS

The snap switch has 90° male quick connect terminals in 1/4" (standard) or 3/16" (optional) sizes. Before pressure is applied to the diaphragm, the switch contacts will be in the deactivated position as shown in Figure 2.

AIR SAMPLING CONNECTION

Series NS2 switches are available with many different types of sample line connections that accept a wide range of flexible and rigid sample line tubing. See Figure 3.

AIR SAMPLING METHOD

The High or Positive inlet (P1) is black and the Low or Negative inlet (P2) is gray. Connect the sample lines as follows:

Positive Pressure Only: Connect the sample line to P1; P2 remains open to the atmosphere.

Negative Pressure Only: Connect the sample line to P2; P1 remains open to the atmosphere.

Two Negative Samples: Connect higher negative sample to P2; lower sample to P1.

Two Positive Samples: Connect higher positive sample to P1; lower sample to P2.

One Positive and One Negative: Connect positive sample to P1; connect negative sample to P2.