DayTronic IL78A, Manual

b

c

Remote Calibration Check:

 The instrument can be placed in the calibration mode (positive or negative) by 

shorting terminals Power Common and SHP for positive or SHN for negative  on  the  lower  I/O  connector. 
Figure  4  indicates  two  methods  of  remotely  entering  the  calibration  mode  (external  switch,  or  push 
button  control).  The  Remote  Cal  function  provides  a  convenient  method  of  periodically  monitoring 
calibration  of  the  instrument  in  the  positive  or  negative  realm.

Master/Slave Connections

. 

   : When more than one IL78A is being used in a measurement setup 

(instruments  are  closely  mounted  or  the  transducer  cabling  is  in  a  common  conduit  or raceway), 
beat frequencies may be produced from the 3-kHz oscillators used in the instruments to develop the 
excitation. To prevent beat frequencies from occur-ring, one unit can be designated the master, and 
the remaining units can be driven from the oscillator contained in the master unit. The remaining 
units are designated as slave instruments. To perform master/slave wiring, refer to Figure 7.

3.

CALIBRATION 

(cont.)

Switch 1 - Mode - 

current (I) or voltage analog output

Switch 2 - Volts  - 

+/- 5 or +/- 10 Vdc when mode is voltage

Switch 3 - Current - 

4-12-20 or 4-20mA when mode is current

Switch 4 - Filter - 

650 Hz or 100 Hz at 3 db, for 100 Hz switch 5 must be set down 

Switch 5 - Filter - 

10 Hz or 100 Hz at 3 db, for 100 Hz switch 4 must be set down

Switch 6 - Sync - 

excitaton clock to slave from a master module or to be master

Switch 7 - Zero Adj. - 

extended (100%) or normal (25%) zero authority 

Switch 8 - Aux Output - 

SYC terminal output for use by other modules

Coarse Zero - 

16 position switch adjustment for stepped zero 

balance control marked for calibration default position

Fine Zero - 

18 turn potentiometer for fine zero balance control

Coarse Span - 

16 position switch adjustment for stepped gain 

contr ol marked for calibration default position

Fine Span - 

18 turn potentiometer for fine gain - span control

Symmetry - 

adjust the negative output span to be equal

 to the positive output

Phase - 

adjustment for phasing the AC modulated signal to its 

highest level at load

Over Range - 

indicates when the analog output is 2% greater 

than mode selected

Power - 

indicates the power input voltage is ON

Fig. 2 Front Panel Settings and Indicators

Calibration  IL78A.3

AC Strain Gage Conditioner

Module

IL78A