Control Applications; Ddc Control Of High Performance Substation - Honeywell AUTOMATIC CONTROL SI Edition Engineering Manual

The primary side includes shut off valves, differential
pressure, and flow control equipment provide safety functions
and a required differential pressure or flow. Heat metering is
also included. The water flow here is divided into two parts.
The HEX transfers the heat from the primary system to the
DHW loop. A valve placed in series with the HEX controls the
flow. The other part of the primary flow enters the secondary
PRIMARY SUPPLY
PRIMARY RETURN

CONTROL APPLICATIONS

DDC CONTROL OF HIGH PERFORMANCE SUBSTATION

Reference
LIC 56 Water level supervision & control
LIC 63 Water level supervision & control
PDIC 14 Primary differential pressure
PDIC 45 Secondary differential pressure
PI 13 PSF pressure
PI 16 PRF pressure (internal)
PI 46 SRF pressure
PI 110 PRF pressure (outdoor)
PIC 57 SSF pressure
PLC S9000 Supervisory Control
PSA+ 52 Safety pressure limit (refill pipe)
PSA+ 58 Safety pressure limit (SSF)
PZA+ 24 Safety pressure limit (high)
PZA+ 34 Safety pressure limit (high)
PZA+ 43 Safety pressure limit (SSF high)
PZA-27 Safety pressure limit (low)
PZA-37 Safety pressure limit (low)
PZA–42 Safety pressure limit (SSF total low)
QIR 53 Metering refill quantity
QIR 62 Cold water metering
QIR 111 Heat metering
TI 01 Outdoor air temperature
TI 12 PSF temperature
TI 15 PRF temperature (total flow)
TI 21 PRF temperature (HEX 1)
ENGINEERING MANUAL OF AUTOMATIC CONTROL
CHILLER, BOILER, AND DISTRIBUTION SYSTEM CONTROL APPLICATIONS
PRESSURE
CONTROL
P=CONSTANT
HEAT
EXCHANGER
(DHW)
Fig. 135. Hybrid Heat Transfer Substation.
Table 10. Description of Figure 136 Reference Points.
Description
circuit and transfers the heat to the consumer directly. The
supply flow temperature is controlled by one three-way valve,
two two-way valves, or one jet pump making an additional
circulation pump redundant.
In cases without a jet pump, circulation pumps provide the
needed differential pressure.
Reference
TI 31 PRF temperature (HEX 12)
TI 47 SRF temperature
TIC 28 SSF temperature (HEX 1)
TIC 38 SSF temperature (HEX 12)
TIC 44 SSF temperature
TSA+ 22 High temperature limit Primary Return Flow
Heat exchanger 1 (PRF HEX 1)
TSA+ 32 High temperature limit (PRF HEX 12)
TSA+ 25 High temperature limit (SSF HEX 1)
TSA+ 35 High temperature limit (SSF HEX 12)
TZA+ 26 Safety temperature limit (SSF HEX 1, locked)
TZA+36 High temperature limit (SSF HEX 12, locked)
TZA+ 41 Safety temperature limit (SSF total, high)
Y 11 Actuator valve Primary Supply Flow (PSF)
Y 17, Y 18 Actuator control valve (PDPC)
Y 19 Safety close off valve
Y 23 Actuator control valve
Y 29 Damper (secondary flow, HEX 1)
Y 33 Actuator control valve
Y 39 Damper (secondary flow, HEX 12)
Y 48, Y 49 Secondary flow circulating pumps
Y 51 Actuator valve (water refill from PRF)
Y 54 Vent valve
Y 55 Compressor
Y 61 Actuator valve (cold water refill)
Y 64 Feed water pump
387
DHW SUPPLY
DHW RECIRCULATED/
COLD WATER
HEATING SUPPLY
HEATING RETURN
M11433
Description