DMT 720MO, Руководство пользователя

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13 TISSUE BATH MYOGRAPH SYSTEM - 720MO - USER GUIDE
Figure 4.1 Close-up of transducer pin from outside.
The arrow indicates the place that the grease needs to be applied to prevent water and buffer from damaging the transducer.
4.2 Maintenance of the force transducer
The force transducer is the most delicate and fragile component of the Tissue Bath. Extreme care should be used when handling
or touching the force transducers. As a part of daily maintenance, inspect the grease around the transducer pin extending from
the transducer housing pinhole before starting any experiment, see figure 4.1 below. Insufficient grease in this area will allow
buffer and water to enter the transducer housing and causing damage to the force transducer.
IMPORTANT NOTES
DMT RECOMMENDS THAT THE HIGH VACUUM GREASE SEALING THE TRANSDUCER PINHOLE IS CHECKED AND SEALED AT
LEAST ONCE A WEEK, ESPECIALLY IF THE TISSUE BATH IS USED FREQUENTLY.
DMT TAKES NO RESPONSIBILITY FOR THE USE OF ANY OTHER KINDS OF HIGH VACUUM GREASE OTHER THAN THE ONE
AVAILABLE FROM DMT.
DMT TAKES NO RESPONSIBILITY FOR ANY KIND OF DAMAGE TO THE FORCE TRANSDUCERS.
4.2.1 Checking the force transducer
The force transducer is a strain gauge connected to a Wheatstone bridge. The force transducers for each chamber are housed
in a separate, protective compartment. While the protective cover offers some mechanical protection for the force transducers,
they are still very vulnerable to applied forces exceeding 1 Newton (100 grams) or fluid running into the transducer compartment
due to insufficient greasing of the transducer pinhole.
If the force readings on the Multi Interface appear unstable or noisy, then first check that the chambers are connected properly
to the Multi Interface and that the chambers are plugged all the way into the Multi Interface. If the force reading(s) are still unsta-
ble or noisy, then perform a new calibration as described in chapter 3.5.1 in Multi Myograph
System User Manual.
During the new calibration, monitor the relative force reading values in the Force Calibration sub-menu on the Multi Interface
(Steps 4 and 5 of the force calibration procedure). The normal operating values for the force transducer during calibration should
be between 3000 and 3500.
• If the value is 0, a single digit, or a three digit number, the force transducer is broken and needs to be replaced.
• If the value is less than 2000 or greater than 4500, the force transducer has been broken and needs to be shipped to DMT
for further test and a temperature compensation.
• If the message “OFF” is displayed on the main page of the Multi Interface, even though the Tissue Bath is plugged in at the
rear of the Multi Interface, the force transducer is broken and needs to be replaced. In addition, if the force reading(s) ap-
pear yellow in color, cannot be reset to zero, AND the transducer cannot be recalibrated, the force transducer is broken and
needs to be replaced.
If any other problems related to the force transducer are encountered, please contact DMT for advice or further instructions.