CDHF-SVU01C-EN
14
General
Information
CTV Duplex Sequence Of Operation
This section will provide basic
information on chiller operation for
common events. With
microelectronic controls, ladder
diagrams cannot show today’s
complex logic, as the control
functions are much more involved
than older pneumatic or solid state
controls. Adaptive control algorithms
can also complicate the exact
sequence of operation. This section
and its diagrams attempt to illustrate
common control sequences.
The Sequence of Events diagrams
use the following KEY:
Software States: (Figure 7)
There are five generic states that the
software can be in:
1. Power Up, Stopped, Starting,
Running, Stopping
Timeline Text: (Figures 8-11)
The large timeline cylinder indicates
the upper level operating mode, as it
would be viewed on DynaView. Text
in Parentheses indicates sub-mode
text as viewed on DynaView. Text
above the timeline cylinder is used to
illustrate inputs to the Main
Processor. This may include User
input to the DynaView Touch pad,
Control inputs from sensors, or
Control Inputs from a Generic BAS.
Boxes indicate Control actions such
as Turning on Relays, or moving the
Inlet Guide Vanes. Smaller cylinders
indicate diagnostic checks, Text
indicates time based functions, Solid
double arrows indicate fixed timers,
Dashed double arrows indicate
variable timers
Power Up Diagram:
The Power up chart shows the
respective DynaView screens during
a power up of the main processor.
This process takes from 30 to 50
seconds depending on the number
of installed Options. On all power
ups, the software model always will
transition through the ‘Stopped’
Software state independent of the last
mode. If the last mode before power
down was ‘Auto’, the transition from
‘Stopped’ to ‘Starting’ occurs, but it
is not apparent to the user.
Software Operation Overview
Diagram:
The Software Operation Overview is
a diagram of the five possible
software states. This diagram can be
thought of as a State Chart, with the
arrows, and arrow text, depicting the
transitions between states.
The text in the circles are the internal
software designations for each State.
The first line of text in the Circles are
the visible top level operating modes
that can be displayed on Dyna View.
The shading of each software state
circle corresponds to the shading on
the timelines that show the state that
the chiller is in.
Figure 7. Sequence of operation overview.