Bently Nevada 19045, Руководство по установке

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Section 1 - DESCRIPTION
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FUNCTIONAL DESCRIPTION
A functional block diagram of the LVDT internal circuitry is shown in Figure 1-1.
The 24 Vdc supply power is connected to LVDT lead wires. This voltage drives an
oscillator to produce an alternating current. The alternating current is applied to
the primary of the differential transformer. The transformer has two secondary
windings, 180° out of phase, that are coupled to the primary by the movable core.
Core position determines the output voltage amplitude of each secondary. The
secondary outputs are applied to a demodulator which produces a dc voltage
signal. This signal varies in amplitude and polarity from negative, to zero (null), to
positive as the core moves through its operating range in a toward-LVDT
direction. Figure 1-2 is a graph of the output signal of the DC-LVDT models used
with BNC instruments. Output voltage is zero when the core and housing null
centers coincide.
Figure 1-1. DC-LVDT Functional Block Diagram