MACTek BULLET™ – User Manual
DM1101010UAB
Copyright 2009-2010
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external battery or solar cell, and can be used to power off the HART field devices
between measurements.
When used in combination with Burst mode, the Bullet will schedule measurements from
the HART devices connected, and will turn on the loop when a scheduled measurement
is needed. After all the measurements have been read from the connected HART
devices, the Bullet will power off the devices by turning off the “Field Device Power
Control” switch.
For this mode to work properly, the user needs to determine and configure the “Power
On Time” parameter for the connected wired HART field devices.
Field Device Power On Time:
The time in seconds that a HART field device needs to
be powered on in order to obtain an accurate measurement.
Note: Improper selection of the “Power On Time” parameter can lead to a field device
reporting measurements outside of the published tolerances for the device. Consult the
field device documentation or contact the field device vendor to determine this
information.
Field Device Idle Time:
The time in seconds that the field device will remain powered
after an unscheduled event. This event could be a HART query over the WirelessHART
handheld or detection of another HART master trying to communicate (such as a wired
HART handheld). This parameter prevents the Bullet from powering off a field device
when some other master is attempting communication with the field device. This
parameter can generally be left at the default of 60 seconds.
Field Device Estimate On Percentage:
This is the estimated time that the field device
will be powered during normal operation. This is a calculation based upon the Field
Device Power On Time and the Burst mode settings of the Bullet. The lower this value
is, the less amount of power will be used.
Join Device to Network (method)
The Join Device to Network DD Method guides the user through entering in the
WirelessHART network ID and join key, and starting the WirelessHART join procedure.
Network ID
The Network ID is the ID of the WirelessHART Network to join.
Join Key
The Join Key is a 32 character hexadecimal password (broken into four 8 character
blocks) which is used to get access to the WirelessHART network.
