Technical Specifications

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NOTE The Mux hardware re-scan is different from the re-scan performed
by ValVue ESD from the Re-scan button. No communication
between ValVue ESD and any device takes place on the node until
the reset is completed. This can take several minutes, depending
on MUX loading.
Scan Option
The MTL multiplexor has the capability to continually scan the connected Hart devices to
report the results. ValVue ESD does not use this feature, but the option is provided to configure
the multiplexor as needed by other applications.
The multiplexor can be used to request information about HART devices. Select the MUX Reset
popup menu function to issue a reset command to a node of the multiplexor. You are
prompted for the node that is to be reset. When it is reset, the multiplexor node re-scans all of
the devices connected to the node (this hardware rescan is different from the re-scan done by
ValVue ESD from the Re-scan popup menu function). Depending upon the options set for the
multiplexor, this can take a while to complete. No communication can be done with devices on
the selected node until the reset is completed. After the reset is finished, select Re-scan popup
menu function to build a device list.
A device list is arranged in the order found on the multiplexor’s channels. This list can be very
long if there are many connected devices. To find a device by its tag, select the Find by Tag
button to open a text entry dialog. Enter a tag name to allow ValVue ESD to search the device
list for a device with a matching tag. If found, the device is selected and the window scrolled
so that its line is visible.
Selecting the Re-scan popup menu function causes ValVue ESD to build a new device list. All
nodes are checked. If there are a large number of devices connected to the multiplexor, this
function can take some time to complete. When the re-scan is completed, you can optionally
save the device list to a file so that rescanning is not necessary every time ValVue ESD is
started.