KROHNE OPTIMASS with MFC 05x EN User Manual

Page 98

Installation and Operating Instructions OPTIMASS

OPTIMASS 8000 / 9000

Inductance (mH)

Resistance (Ohm)

OPTIMASS

Driver

Sensor A/B

Driver

Sensor A/B

8000 2.2

0.735

12.5

9000 2.6

0.95

• The above data are provided as a rough guide only.
• Driver = White / Brown
• Sensor A = Orange / Black. Sensor B = Grey / Blue
• RTD = Red / Purple (108Ω at 20°C if PT100, 540Ω at 20°C if PT500). Compensation leg = Purple /

Yellow

• Resistance values outside these values could indicate a circuit failure. Meter may be in start-up or have

measuring errors.

• All circuit should be isolated from ground (meter case) and each other: >20MΩ. If circuits are shorting

to ground, meter may be in start-up.

6.4 Replacing the Front End or Back End Electronics

If a failure occurs in one or the other of the above electronics, these can be easily replaced with the
minimum downtime. Please remember to disconnect or switch off the power supply to the meter when
performing these tasks. Please observe the waiting time for Hazardous area approved meters.

To make exchanging the components easy, a copy of the Front End calibration coefficients are stored in
the Back End as well. This facilitates the changes without the necessity of sensor calibration coefficients.

Note:
The following functions must only be performed by qualified personnel.

6.4.1 Replacing the Front End

• Please unscrew the four small screws holding the Front End in place (screws at the rear).
• Take care when removing to ensure that the connections are not damaged.
• Do not lose the gasket.
• Replace with new Front End electronics, ensuring that the gasket is well positioned and the

connections have mated correctly.

• Do not force the connectors.
• Tighten securely.
• It is recommended that some locktite or similar compound is used for the screws.

After power up the measuring system will recognize a hardware change. The display will show Sys.
Changed.

Key Display
Sys.

Changed

→ Select

with

↑ key between

↑

New FE (Front End).

→ Select

with

↑ key between

↑

Sure No

↑

Sure Yes

Accept with

↵

Back End data will be used as master.

The Front End software is downloaded from the Back End electronics automatically. The system is now
ready to measure. It is recommended that a zero calibration is performed if possible.