WattMaster WM-WCC3-TGD-01B - Manual (Page 262)

WCC3.EXE SCREEN DESCRIPTIONS
WCC III Technical Guide 3-148
Analog Global Dual Valve Mode
Dual Valve Mode
Dual Valve is used when two valves are used to control one output
with parallel connection. Normally, one valve is a larger valve and
the other valve is a small valve.
The control input has to be from 0 to 100 with unit %. The valve
size also is based on combined units %. The valve size of both
valves should add up to 100 %. The Global Analog Dual Valve
mode has three stages:
Stage 1: Valve 1 is modulating and Valve 2 is closed.
Stage 2: Valve 1 is closed and Valve 2 is modulating.
Stage 3: Valve 1 is full open and Valve 2 is modulating.
The Dual Valve mode has 5 staging setpoints:
Stage 1 Stage Up setpoint
Stage 2 Stage Up setpoint
Stage 2 Stage Down setpoint
Stage 3 Stage Down setpoint
Stage Time
Stage Time is an internal stage timer counter for deciding whether
to stage to/back next/previous stage. The timer will start to run
when the condition is met, exceeding or dropping below the xx%.
The timer resets when the condition disappears. If the stage timer
exceeds the Stage Time, the Stage changes to next/previous stage.
During Stage 1, when the monitored analog input exceeds the
Stage 1 Stage Up setpoint, the internal stage timer starts to run.
When the internal stage timer exceeds Stage Time, the stage
changes to Stage 2. The stage timer resets to zero when the
monitored analog input is less than the Stage 1 Stage Up setpoint.
During Stage 2, when the monitored analog input exceeds
the Stage 2 Stage Up setpoint, the internal stage timer starts
to run. When the internal stage timer exceeds the Stage Time,
the stage changes to Stage 3. Or when the monitored analog
input drops below Stage 2 Stage Down setpoint, the internal
stage timer starts to run. When the internal stage timer exceeds
the Stage Time, the stage changes to Stage 1. The stage timer
resets to zero when the monitored analog input is between
Stage 2 Stage Down setpoint and Stage 2 Stage Up setpoint.
During Stage 3, when the monitored analog input drops below
the Stage 3 Stage Down setpoint, the internal stage timer starts
to run. When the internal stage timer exceeds the Stage Time, the
stage changes to Stage 2. The stage timer resets to zero when the
monitored analog input is above the Stage 3 Stage Down setpoint.
Since Dual Valve Mode has two outputs, the next very global
analog has to be set to EXTERNAL mode for this Dual Valve
operation to work.