BAS-SVX078E-EN
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Duty Cycles
Indoor temperature control is achieved by duty-cycling the equipment when the load value is less than
100% of the current stage of operation. The duty cycle rate is dependent on the calculated load value.
The illustration below shows the number of cycles at 50% load, for example, LV = 50.
With all PI-based controls, the indoor temperature fluctuates above/below the user-selected setpoint to
maintain comfort in the space. Adjusting the factory Cycles Per Hour (CPH) can affect how tight the unit
operates around the setpoint. The CPH can be adjusted by navigating to
Installer Setup > Equipment
Settings
(Group 2).
•
Factory default for compressor operation = 3 CPH
•
Factory default for indoor heat = 5 CPH
The effects of changing the cycle rates:
•
Lower CPH results in longer run cycles with less cycling, but the indoor temperature may deviate
above/below setpoint.
•
Higher CPH results in tighter indoor temperature control, but shorter and more frequent cycles.
Overshoot Clamp
The Pivot thermostat enforces an Off Cycle anytime the control overshoots more than 2.5°F. Once the
indoor temperature is within 0.75°F of setpoint, an ON Cycle is allowed dependent on load value and
minimum Off times. Refer to the following illustration showing cooling overshoot clamping.
Staging
Stage Thresholds
The threshold that allows operation is a load value greater than 5 and operation is always terminated
with a load value less than 1. In addition, load value determines when additional stages of operation are
requested. To prevent rapid cycling between stages, a stage threshold is enforced. The stage threshold
is dependant on the applied system. See examples of staging thresholds below.
Summary of Contents for Pivot BAYSTAT814 Series
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