Cameron NUFLO 1141C, User Manual

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Scanner 1141 Hardware User Manual
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Analog 4-20 mA Transmitter
Use of conventional 4-20 mA transmitters requires the addition of precision 250-ohm load resistors
on each analog channel (Figure 3.14). Power for the current loop is normally drawn from an external
source.
Anin
Common
4-20 mA
+
Figure 3.14—Wiring diagram for 4-20 mA analog transmitter
In some configurations, sockets on the main board can be used to install the precision resistors.
Sockets are not installed in all configurations.
Table 3.4—Socket Identification
Resource Socket
A09 CN15
A16 CN14
A17 CN13
A10 CN12
A19 CN10
A20 CN9
Frequency Pulse Inputs
The Scanner 1141 frequency pulse inputs interface with a variety of pulse-producing sources including
turbine magnetic pickups, preamplified turbine signals, as well as open collector and contact closures
with a debounce filter. Each of these input types are discussed on the following pages.
Frequency Pulse Input DIP Switch Summary
A six-position DIP switch at the left edge of the main circuit board allows the user to configure the
desired electrical interface.
Resource A07 uses terminals 23-24 and DIP switch 5 (SW5). Resource A14 uses terminals 49-50 and
DIP switch 1 (SW1). If these terminals are not on the main board, the frequency pulse input option is
not installed.
Table 3.5 summarizes the function of each switch on the Frequency Pulse Input switch (SW1 and
SW5):