Taco iWorx PSU1, Application Manual

Page: 23 / 28

iWorx® PSU1
505-012, Effective: August 10, 2012 23
© 2012 Taco Electronic Solutions, Inc.
All Settings
This screen displays all of the controller's settings and provides access to edit all parameters from a single screen.
Some parameters (defaulted as Structure) are described in individual tables below.
Pump Settings
This screen displays PSU1 settings related to this topic and allows access to all of these settings from a single screen.
Setting Range Default Description
Pump Settings Structure N/A General pump settings
Commissioning Structure N/A Pump commissioning settings
Enable Alarm Disabled,
Switch (open),
Switch (closed Disabled Enables monitoring and alarming associated
with the Pump Flow Proof switch
Flow Delay 0 to 180 seconds 15 seconds Amount of time to wait without flow before
signaling pump failure
Thermistor Type PreconII,
PreconIII PreconIII Selects the type of thermistor used for supply
and return water temp
Pump Mod Set Structure Pump modulation settings
Low Temp Setting 0.01 to 50 °F 0.01 °F Sets the minimum temperature at which low
temperature circulation activates. If set to
0.01°F, then this feature is disabled.
Water Temp Alm Structure N/A
Auto Recovery Structure N/A Auto Flow Recovery settings.
Setting Range Default Description
Operational Mode Standby,
Single,
Equal Runtime,
2 Stage Single Operating sequences of the two pumps
Const Pump Circ Off, On Off Causes pumps to run continuously, regard-
less of demand
Lead Pump Sel Pump 1,
Pump 2,
Lowest Hours,
Alternating Pump 1 Determines the pump selection method to
use when a new pump must be started.
Pre Purge Time 0 to 100 seconds 10 seconds Time primary pump runs before starting a
boiler stage (must be in sync with the BLMC)
to allow accurate temperature measurement.
Post Purge Time 0 to 255 minutes 5 minutes Time primary pump runs after the demand is
off to dissipate heat and allow pump speed to
return to a minimum value.
Max Runtime 1 to 255 hours 168 hours Amount of run time by which the lead pump
exceeds the lag pump before swapping lead
and lag.
Differential Temp 0 to 40 °F (0 to 22.2 °C) 40 °F (22.2 °C) Primary loop Delta T at which the second
pump is turned on or the desired primary loop
Delta T in single stage modulated mode. The
Absolute value of Delta T is always used
when comparing against this setting.
Pump Exercise Off, On Off If “On,” pumps are run sequentially for 15
seconds every week.
Operational Type Switching,
Modulated Switching Turns on modulated outputs. Not available in
2 Stage mode.