Yokogawa DM8C/VD6 Liquid Density Analyzer User Manual

Page 47

< 4. OPERATION >

4-5

IM 12T03A01-02E

Function No. ‘7’: Sets density of calibration solution 2

Density data (g/cm

) for the 2nd calibration (calibration solution 2) of two-point calibration can be

input. As a rule, the input density is data at the same reference temperature as that of ‘4’.

(Note) If relation between temperature and density is well known, a density at a temperature can

be input. However, the density data at the reference temperature which is same as that of
‘4’ is recommended to achieve accurate calibration.

Function No. ‘8’: Sets temperature of calibration solution 2

Enter the temperature of calibration solution 2 of which density at the reference temperature is
set at ‘7’.

Function No. ‘9’: Sets temperature coeffi cient of calibratio solution 2

Enter the value which is -100000 times the temperature coeffi cient (g/cm

/°C) of the calibration

solution 2.

Function No. ‘A’: Starts calibration 2 (press SET key)

Pressing “SET” key executes 2nd calibration computation of two-point calibration.

(3) Maintenance mode (MAINT): Mode for adjusting and checking operating conditions.

During this mode, analog and digital outputs are held (at the value just before holding).

Function No. in maintenance mode is from ‘1.’ to ‘D.’ (see table 4.1).

Function No. ‘1.’: Canceles protect (enter 77)

Function to avoid data changing due to carelessness. When “0” is displayed, a function No. is
not entered. To release the protection, display “77” and press “SET” key. When protecting again,
display any number other than “77” (for example 78) and press “SET” key. This operation is
invalid unless some operation is made after the protection release (for example, setting function
No. ‘2’).

Function No. ‘2.’: Displays frequency (density)

Checks operation of this converter. Frequency corresponding to measured density are
displayed. When the converter is normal, the frequency ranges from 600 to 700 Hz to 1000 or
1500 Hz.

(Note) Displayed frequency varies with measured density, liquid temperature and detector

constant. If density is 0.5 to 2.0 g/cm

, temperature is 25 °C, detector constant (A) is 17074

and detector constant (B) is 36384, the frequency is 640 to 1400 Hz for normal operation.

Function No. ‘3.’: Displays frequency (temperature)

Checks operation of this converter. A frequency signal converted from liquid temperature voltage
is displayed. If temperature is 25 °C, the frequency is about 25000 to 35000 Hz for normal
operation.

Function No. ‘4.’: Checks output signal

Checks zero point and span of an analog output signal.

(Note) The data at shipping is described in a data sheet in the converter.

Function No. ‘5.’: Checks LED (press SET key)

Function to check LED data display. When “SET” key is pressed, all displays fl ash fi ve times if it
is normal.

Function No. ‘6.’: Sets low limit of the output range

Sets a low limit density value (g/cm

) of an analog output range.