Instruction manual

BRIDGE8

World Precision Instruments 3

S HIELD

- 5 V

+ 5 V

+ OUT

- OUT

TRA NSDUCE R PLUG (S O LDE R SIDE)

G ND

Fig. 2—Wiring schematic for the 8-pin DIN connection.

Positioning the Output to Zero

Insert the transducer plug into the panel transducer input connector. Switch the

Gain Select switch for the channel being used to x10 and set the Bridge switch

to Differential. Turn on the Power switch at the top of the panel. One or both of

the two red Offset Adjust indicator lamps will light if a transducer is plugged into

the appropriate connector on the front panel. Output coaxial connectors for all

channels are located on the rear panel of the instrument. If the – lamp is lit, the

output voltage level is minus. If the + lamp is lit, the output voltage level is positive.

To bring the output voltage level to nearly zero volts, adjust the Offset Adjust knob

above the Gain switch so that both lamps are lit together. A signiﬁcant increase in

the sharpness or resolution of the zero adjustment may be achieved by increasing

the gain to x100.

Bridge Switch

Many transducers conﬁgured as Wheatstone bridges with four resistive elements will

directly access the differential ampliﬁer, as represented in Fig. 3. When the Bridge

switch is in the Differential position, both inputs of the differential ampliﬁer, inverting

and non-inverting, are connected to the signal terminals of the transducer bridge. In

single-ended operation, the inverting input of the differential ampliﬁer is connected

to a variable reference potential leaving the non-inverting input available to the

signal source. In the Gnd (ground) position both the inverting and the non-inverting

inputs are connected to ground.

+ out

- out

SHIELD

+5 v

-5 v

Fig. 3—This transducer is conﬁgured as a Wheatstone bridge with four resistive elements.