1 For technical parameter and connection terminal diagram for Type LWF-P-1
pulse output pre-amplifier, see Figure 8-1.
（1）Through thread M14*1, Type LWF-P-1 pre-amplifier is screwed into installation
thread holes on the body of the turbine flow meter, and then is locked with locknuts.It
is a kind of small-sized amplifier of low driving power, suitable for application in association
with normal display instruments.
The output signals are delivered by the connector plugs through 3-wire shielded cable,
with metal shielded network grounded. The connection is as per Figure 8-1.
● a. Connection terminal diagram ●b. Connection Terminal Diagram for Connecting
for Aviation Connector Plugs Terminals
Figure 8-1 Connection Terminal Diagram of Type LWF－P Pre-Amplifier
0 Power supply source: VDD is the nominal value 12VDC
0 Output signal: square wave
Low electrical level：≤1VDC
High electrical level：Power supply voltage VDD-3VDC
Output signal frequency: (at lower limit of flow) not lower than 20Hz
（2） Type LWF-P-2 pulse output pre-amplifier is a preamplifier featuring strong load
capacity and adaptability of power supply source, and it may provide reliable pulse signals
to PLC.
For wiring connection, please see Figure 8-1, in which +12VDC is modified to +24VDC.
0 Power supply source: VDD is the nominal value24VDC
0 Output signal: square wave
Low level：≤1VDC
High level：Power supply voltage VDD-3VDC
Output signal frequency: (at lower limit of flow) not lower than 20Hz
（3）Type LWF-P-3 pulse output preamplifier is a preamplifier designed for high temperature
conditions of materials and structures of the detector parts on the basis of Type LWF-P-2 amplifier.
Under the precondition that the ambient temperature is not higher than 55℃, the medium temperature
may come up to 150℃.