Supplementary Source - Fujitsu Waterstage Comfort Series Maintenance Document

Split system single phase type

4 4 3 Supplementary source

A supplementary producer can be operated in addition
to the main producer (heat pump)
Release of the supplementary producer depends on a
number of parameters a detailed description of which is
given on the following pages
• Release is effected via release relay QX2
• 2-position control is effected via control relay QX3
• Ux can be used to transmit the supplementary source
a DC 0 10 V signal for the required temperature/output
setpoint
Line N° Programming line
3692 With DHW charging
Defines the release of the supplementary source for
DHW charging:
• Locked
The supplementary source will not be released
• Substitute
The supplementary source is released only if the main
source cannot be put into operation (e g in the event
of fault)
• Complement
The supplementary producer is released if the output of
the main producer is not sufficient.
• Instantly
The supplementary source will always be released
Line N° Programming line
3700 Release below outside temperature
3701 Release under outside temperature
Operation of the supplementary source is released only
when the composite outside temperature lies above or
below the set temperature limit
This enables the supplementary source to lock in a
selected outside temperature range to ensure bivalent
operation of supplementary source and heat pump
To ensure continuous release of the supplementary
source, setting "---" must be selected on the respective
operating lines
If both release values are enabled, the outside
temperature must satisfy both criteria, thus ensuring
release of the supplementary source
Maintenance document "1792 - EN"
Overtemperature protection
Line N° Programming line
3705 Overrun time
Overrun time of release for the external source: If the
integral indicates another heat deficit before the overrun
time has elapsed, the release remains activated
If the set overrun time elapses before the common flow
temperature drops below the common flow temperature
setpoint, the release is deactivated also
Flow control
Line N° Programming line
3720 Switching integral
3723 Locking time
Switching integral
The temperature-time integral is a continuous summation
of the temperature differential over time In this case,
the decisive criterion is the difference by which the
temperature lies above or below the common flow
temperature setpoint
The temperature-time integral gives consideration
not only to the period of time, but also to the extent of
over-/undershoot This means that when the crossing is
significant, the supplementary source is released earlier,
or locked earlier, than with minor crossings
QX2
QX3
TVx Actual value of flow temperature
TVw Flow temperature setpoint
+ Int Surplus integral
- Int Deficit integral
t1 Overrun time (not completed)
t2 Overrun time (fully completed)
QX2 Release output QX2
QX3 Control QX3
Locking time
The locking time enables the heat pump to reach a
stable operating state before the supplementary source
is allowed to switch on The supplementary source is
released only when the locking time has elapsed The
locking time starts as soon as a valid flow temperature
setpoint is available Calculation of the release integral
starts only when the locking time has elapsed
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