Dwyer Series PUB - Manual (Page 8)

1: General Description
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1.4 PUB Instrument
The PUB is a microprocessor controlled instrument operated through a menu system using an inbuilt LCD display
and keypad. It can be used to display the instantaneous fluid flow rate or velocity, together with totalized values.
The instrument can also provide a variable current or variable ‘pulse’ (volumetric of frequency) output that is
proportional to the detected flow rate. This output can be calibrated to suit a particular flow range and used with a
range of external interface devices such as those found in building management or site monitoring systems.
1.4.1 Connectors
Figure 1.3 Instrument details
Transducer connections
The transducers are connected to two color-coded miniature coaxial sockets located on the top of the instrument.
Using the red/blue connector cables provided, the upstream transducer should always be connected to the RED
socket and the downstream transducer to the BLUE one for a positive flow reading. It is safe to connect or
disconnect the cable while the instrument is switched on.
4 to 20 mA and Pulse output connection
The 4 to 20mA / ‘pulse’ output cable should be connected to the green 7-pin connector on the top of the
flowmeter, as shown in Figure 1.3. A single cable that can be adapted for use for either of these output functions
is included in the PUB kit. The ‘tails’ on the free end of the cable must be terminated to suit the intended
application.
Red – 4 to 20 mA positive
Black – 4 to 20 mA negative
White – Pulse output
Green – Pulse return
Thick Black – Cable screen
Battery charger connection
The supplied battery charger is connected to the instrument by means of the gray 2-pin connector on the bottom
of the unit, as shown in Figure 1.3.
Note: The above connectors have different key-ways to prevent incorrect cable connection.
Keypad
LCD Display
Battery Charger
4-20mA / Pulse Output Transducer Cables
Reset pin-hole