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5.2.1
– <Control>
In the Control screen all the necessary information about
the instantaneous performance of DynaFLO can be viewed.
<DHW Outlet Temp.> displays the reading from the RTD
sensor mounted on the outlet (bottom pipe) of the DHW side
of DynaFLO. <Setpoint> is a touch-screen display that
shows the current user-selectable setpoint which could be
changed by just touching it. This setpoint sets the target
temperature of the DHW outlet. The control will modulate
the actuator to regulate the amount of heat that is allowed
to enter the heat exchanger in order to always keep the
DHW outlet temperature /-1°F in steady-state.
NOTE
IF THE CONTROL IS SET TO OPERATE IN ANY
<Remote> MODE <Setpoint> CANNOT BE
CHANGED FROM THE SCREEN.
When the control is in <Remote_Direct> or <Remote_SP>
mode, the setpoint can only be changed by sending a
Modbus command from a master. The <Actuator Position>
displays the position of the three-way electro-hydraulic
actuator mounted on the boiler side of the DynaFLO. This
position is displayed in percentage. 100% means the
actuator is fully open, 0% means the actuator is closed and
the heat exchanger is bypassed. This display is greyed out
in all modes except in <Local_Manual>. As mentioned
before, the PID loop keeps comparing the outlet
temperature to the target setpoint, and it outputs a signal to
the
actuator
correspondingly.
However,
when
in
<Local_Manual> the automatic function of the built-in PID
is bypassed and user can manually control the position of
the actuator. In that case the <Actuator Position> display
stops being greyed out to indicate that the actuator is not
being controlled by the local built-in PID. In that case the
user can insert the position by simply touching the
<Actuator Position> display.
On the right
hand side under “Control Mode” there are four
options. The four options are generally distinguished by
whether the performance is controlled locally by the PLC or
remotely
through
Modbus.
When
control
is
in
<Local_Manual> or <Local_Auto> important parameters
vital to maintaining the target DHW outlet temperature such
as PID, setpoint and actuator’s position can be configured
locally
from
the
touch-screen.
However
when
<Remote_Direct> or <Remote_SP> is selected, those
parameters can only be configured by sending Modbus
commands.
The first option, <Local_Manual> as mentioned bypasses
the local built in PID and makes the <Actuator Position>
display touch accessible such that the user can control the
actuator by inserting the position into this display. This
could become useful in calibrating or troubleshooting the
actuator.
<Local_Auto> will disable the touch accessibility of the
<Actuator Position> (display becomes greyed out). In this
case the local built-in PID controls the actuator position and
<Actuator Position> just displays the current position of the
actuator that is being changed by the built-in PID on the
control. The performance of the built in PID is controlled by
<P> for proportional, <I> for integration, and <D> for
derivative that are located in < PID Parameters> in <PID
Configuration> in <Setup>. However access to these
parameters is only available with a factory level password
as these parameters are not recommended to change.
<Remote_Setpoint> is similar to <Local_Auto> in a sense
that the local built-in PID integrated in the control operates
the actuator position and thereby maintaining the target
outlet temperature. While the local PID on the control is
being used, the <Setpoint> becomes greyed out since it is
configured by a Modbus command sent from a Modbus
Master.
The alarm indicator display located on the top right corner
of the screen indicates the status of alarms. If there is an
active alarm that is not yet acknowledged, the display
shows <Unack’d Alarm>. In this case going to the <Alarm>
screen located on the Start-Up display shows the details of
active alarms at which point they could become
acknowledged. More details regarding alarms are
explained in the next section. If active alarms are
acknowledged the alarm indicator displays <
Ack’d Alarm>,
if there are no active alarms the indicator displays <No
Alarms>.
5.2.2
– <Alarm>
The <Alarm> screen displays active alarms, regardless of
whether they are acknowledged yet or not. Details about
each specific active alarm is shown in
the “Alarm Details”
screen, details such as name of the alarm, priority level,
time of trigger and whether the alarm is acknowledged or
not. Unacknowledged alarms will appear with an “Ack”
button on the bottom left corner of the screen. Pressing the
