Functions; Input; Output; Preheating - KYOWA DPM-900 Series Instruction Manual

5. FUNCTIONS

This chapter describes all the DPM-900/950 series functions in detail as well as advanced usage.

5-1 INPUT

The DPM-900/950 series is designed exclusively for measuring strain. The connectable sensors are as
follows.
Strain gage bridge box
When measuring strain by using the strain gage, use the bridge box.
In addition, purchase the bridge box.
For how to use the bridge box, read "6-1 BRIDGE BOX."
Strain gage transducer
For how to connect the strain gage transducer, read "4-1 CONNECTION OF INPUT."
NOTE
Avoid using instruments or sensors other than the above, or else the DPM-900/950 series will
not function properly. Also avoid connecting one input to multiple DPM-900/950 series units, or
else the DPM-900/950 series will get out of order.
When setting the minimum internal gain at excitation voltage 2 Vrms, the maximum input is
approximately ±50000 µm/m. However, it is capable of inputting approximately up to ±130000
µm/m by conducting the sensitivity fine adjustment but the sensitivity at that time is not
guaranteed.
The maximum output of the DPM-900/950 series is ±10 V. Where a large amount of strain is
input and exceeds the allowable range of the maximum output, the indication on the panel meter
blinks. If it occurred, decrease the internal gain till the indication stops blinking.
When using a bridge box, be sure also to use shielded cables to connect strain gages to the
DPM-900/950 series in order to reduce induction nose. If a parallel vinyl cable is used, the
performance of the amplifier cannot be guaranteed.

5-2 OUTPUT

The DPM-900/950 series is provided with 2 independent output systems. The 2 output terminals can be
connected to 2 different external instruments. Even if one output system should get out of order, it does not
affect the other.
OUTPUT A and OUTPUT B have the following characteristics.
Over ±10V output possible for over 5 kohm load.
The output level can be set up by the internal gain setting and conducting the sensitivity fine adjustment.
The zero point can be adjusted by the zero adjustment.
However, OUTPUT A and OUTPUT B cannot be adjusted separately about the output level and zero point.

5-3 PREHEATING

When once the DPM-900/950 series has been turned ON, it will be ready for operation after 5 seconds.
Note that the internal electrical parts and semiconductors cannot acquire the thermal stability immediately
after switching the power ON. Unless the OCS circuit, especially reaches the thermal stability, a change in
the sensitivity or a drift of the zero point can be changed. Carry out preheating
for stable measurement.
18
*7
for about 30 to 60 minutes