Shed - Honeywell UDC2300 Product Manual

3.8

Shed

What is Shed?
Shed time
Shed controller mode
and output level
Shed setpoint recall
How to enter this
information
10/00 RS422/485 ASCII Communications Option Product Manual
Shed happens when the controller, which has been working in "Slave,"
reverts to "Stand Alone" mode. Upon receiving a "Slave" message, the
controller resets the "SHED TIMER." If this timer expires before the next
valid message, the controller goes to stand alone operation. When the host
reconnects with a valid message, the response will indicate as 8 at the
third digit to indicate a restart after shed.
Thus SHED acts as a safeguard in case the computer or communications
link fail. If something prevents the computer from communicating with
the controller the device returns to the local control mode. The local
operator is then able to regain control over the controller and operate it by
the keyboard.
Shed Time works like a timer. The number selected will represent how
many sample periods there will be before the controller sheds from
computer control. You can configure the shed time to be one that is
between 1/3 second and approximately 83 seconds. 0 = No Shed.
This determines the mode of local control whenever the controller is shed
from the communication link.
This determines what setpoint will be used if the controller is shed from
the communications link.
Refer to "Preparing the Controller for Communications" in this section for
these selections and procedure for entering the information into the
controller.
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