OPERATION
6
111
RM640
www.honeywellprocess.com
34-VF-25-131 iss.1 GLO Feb 2019 US
6.4.7 How to measure correctly in silos with curved or conical bottoms
It is possible that the device cannot find the bottom of the silo if it is installed in a silo with a dish-
shaped or conical bottom. The form of the silo bottom causes a delayed radar reflection and the
device will display the error message "Measurement is lost in the tank bottom".
You can offset the tank bottom reference point to find the delayed radar reflection. Obey the
instructions that follow:
•
Measure the true tank height with a different measurement method.
•
Empty the silo.
•
Enter Program mode and go to menu item C.1.2 Tank Height. Push the [>>>>] button.
•
Enter the password used at this time for the "Expert" access level. If it is the default password,
enter "0058". Push [
^
^
^
^
] and then [>>>>].
•
Increase the value in menu item C.1.2 Tank Height. This value must be a minimum of 20%
more than the true tank height.
•
Go to a measurement page in Normal mode that shows the distance. Make a note of the
distance of the reflection measured by the device.
i
This is the delayed radar reflection. The distance shown will be the new tank height.
•
Subtract the distance to the reflection from the true silo height.
•
Go to menu item C1.11 Tank Bottom Offset (Program Mode > Full Setup > Install.
Program Mode > Full Setup > Install.
Program Mode > Full Setup > Install.
Program Mode > Full Setup > Install.
Parameters > Tank Bottom Offset
Parameters > Tank Bottom Offset
Parameters > Tank Bottom Offset
Parameters > Tank Bottom Offset).
•
Type in the difference you calculated as a negative value.
i
A negative value will move the reference point above the silo bottom (as given in menu item
C.1.2 Tank Height).
•
Type in the distance that was shown in Normal mode.
•
Push 4 × [
^
^
^
^
] to exit to the "Save Configuration?" window.
•
Select Yes
Yes
Yes
Yes and push [
^
^
^
^
].
i
The device will go back to Normal mode.
6.4.8 How to make a filter to remove radar signal interference
If the device measures level in a silo that contains obstructions (ladder, supports etc.), these
objects can cause radar signal interference (parasitic signals). You can use the empty spectrum
function (menu A4.2) in the Quick Setup menu to make a filter to remove radar signal
interference.
INFORMATION!
For more data on menu items, refer to Function description on page 80
–
table C: Full Setup.
INFORMATION!
We recommend that you do an empty spectrum scan when the silo is empty and all the moving
parts are in operation.
Summary of Contents for RM640
Page 4: ...4 www honeywellprocess com 34 VF 25 131 iss 1 GLO Feb 2019 US ABOUT THIS DOCUMENT RM640 ...
Page 20: ...1 SAFETY INSTRUCTIONS 20 RM640 www honeywellprocess com 34 VF 25 131 iss 1 GLO Feb 2019 US ...
Page 56: ...4 ELECTRICAL CONNECTIONS 56 RM640 www honeywellprocess com 34 VF 25 131 iss 1 GLO Feb 2019 US ...
Page 120: ...6 OPERATION 120 RM640 www honeywellprocess com 34 VF 25 131 iss 1 GLO Feb 2019 US ...
Page 182: ...10 APPENDIX 182 RM640 www honeywellprocess com 34 VF 25 131 iss 1 GLO Feb 2019 US ...
Page 183: ...APPENDIX 10 183 RM640 www honeywellprocess com 34 VF 25 131 iss 1 GLO Feb 2019 US ...
