ircon Modline 4, Installation And Operation Manual

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Section 2 - INSTALLATION
2.5 MULTIPLE LOOP SYSTEMS
Fig. 2.3 is an example of a multiple loop system. Two
MODLINE 4 loops are operated from a single power
supply. An arrangement of this type is suitable for measuring
temperatures at two or more stations with an independent
readout for each station. The advantage is the economy of a
single power supply for all loops.
An important consideration in this system is the current capacity
of the power supply. For example, if loops A and B in Fig. 2.3
are both measuring full scale temperature, currents 1
A
and 1
B
will be 20 mA for a total supply current of 40 mA.
The IRCON model PS
4
-
2
4 power supply has a current
capacity of 200 mA giving it the capability of powering up to
ten MODLINE 4 loops.
2. 6 SWITCHED MODLINE 4 SYSTEM
FIG. 2.3 MULTIPLE LOOPS OPERATED
FROM SINGLE SUPPLY
Sometimes you can gain economy or efficiency by switching
between circuit components. Fig 2.4 shows how this idea might
be used to switch a single indicator and power supply to either of
two MODLINE 4 units. This time-sharing system permits
measuring the temperature at either of two stations on a single
indicator.
The switching system shows consists of a double pole, double
throw switch which allows simultaneous switching of both
MODLINE 4 output leads. The switch can be a manual or
an automatically controlled switch or a set of appropriate
relay contacts.
NOTE: These illustrations give you an idea of how
versatile MODLINE 4 can be in system design. Our systems
give you just about any results you’re looking for. If you need
qualified help in choosing components or planning your
system, contact IRCON Applications Engineering
.
.
FIG. 2.4 SWITCHED MODLINE 4 UNITS
2-4
®