TEMPERATURE DETECTION CIRCUITRY
Temperature Detectors
TEMPERATURE DETECTION CIRCUITRY
The bridge circuit is used whenever extremely accurate resistance measurements
are required (such as RTD measurements).
EO 1.9
Given a simplified schematic diagram of a basic bridge
circuit, STATE
the
purpose
of
the
following
components:
a.
R1 and R2
b.
Rx
c.
Adjustable resistor
d.
Sensitive ammeter
EO 1.10
DESCRIBE the bridge circuit conditions that create a
balanced bridge.
EO 1.11
Given a block diagram of a basic temperature
instrument detection and control system, STATE the
purpose of the following blocks:
a.
RTD
b.
Bridge circuit
c.
DC-AC converter
d.
Amplifier
e.
Balancing motor/mechanical linkage
EO 1.12
DESCRIBE the temperature instrument indication(s) for
the following circuit faults:
a.
Short circuit
b.
Open circuit
EO 1.13
EXPLAIN the three methods of bridge circuit
compensation for changes in ambient temperature.
Bridge Circuit Construction
Figure 8 shows a basic bridge circuit which consists of three known resistances, R1, R2, and R3
(variable), an unknown variable resistor RX (RTD), a source of voltage, and a sensitive ammeter.
IC-01
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