Carrier WEATHERMASTER 48/50Z030-105 - Manual (Page 46)

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COOL or a HIGH COOL mode and maintain a low or high
cool supply air set point.
• C.TYP = 4 (TSTAT – 2 STG)
This configuration will force the control to monitor the ther-
mostat inputs to make a determination of mode.
• C.TYP = 5 (SPT – MULTI)
This configuration will force the control to monitor a space
temperature sensor to make a determination of mode. Un-
like traditional 2-stage space temperature control, the unit is
allowed to use multiple stages of cooling control and per-
form VAV style operation. The control will be able to call
out a LOW COOL or a HIGH COOL mode and maintain a
low or high cool supply air set point.
• C.TYP = 6 (SPT – 2 STG)
This configuration will force the control to monitor the
space temperature sensor to make a determination of mode and
allow two stages of cooling.
MACHINE DEPENDENT CONFIGURATIONS — Some
configurations are linked to the physical unit and must not be
changed. The configurations are provided in case a field
replacement of a board occurs and the settings are not
preserved by the download process of the new software. The
following configurations apply to all machine control types
(C.TYP) except 4 and 6. These configurations are located at the
local display under Configuration → UNIT. See Table 34.
Table 34 — Machine Dependent Configurations
*Dependent on unit.
Unit Size (SIZE) — There are several unit sizes (tons) for the
Z Series control. Make sure this configuration matches the size
called out by the model number of the unit. This is important as
the cooling stage tables are directly determined based on both
the SIZE and 50.HZ configurations.
50 Hertz Unit? (50.HZ) — Some units are designed to run at
50 Hertz instead of 60 Hertz. Make sure this configuration
matches the frequency called out by the model number of the
unit. This is important as the cooling stage tables are directly
determined based on both the SIZE and 50.HZ configurations.
SET POINTS — The set points for both cooling and heating
are located at the local display under Setpoints. See Table 35.
SUPPLY AIR RESET CONFIGURATION — Supply air
reset can be used to modify the current cooling supply air set
point. Supply air reset is applicable to control types, C.TYP =
1,2,3, and 5. The configurations for reset can be found at the
local display under Configuration → EDT.R. See Table 36.
EDT Reset Configuration (RS.CF) — This configuration ap-
plies to several machine control types (Configuration → UNIT
→ C.TYP = 1,2,3, and 5).
• 0 = NO RESET
No supply air reset is in effect
• 1 = SPT RESET
Space temperature will be used as the reset control variable
along with both RTIO and LIMT in the calculation of the
final amount of reset to be applied (Inputs → RSET
→ SA.S.R).
• 2 = RAT RESET
Return-air temperature will be used as the reset control vari-
able along with both RTIO and LIMT in the calculation of
the final amount of reset to be applied (Inputs → RSET →
SA.S.R).
• 3 = 3RD PARTY RESET
The reset value is determined by a 4 to 20 mA third party
input. An input of 4 mA would correspond to 0º F reset. An
input of 20 mA would correspond to 20º F reset. Configur-
ing the control for this option will cause RES.S to become
enabled automatically with the CEM board. To avoid
alarms make sure the CEM board and third party input are
connected first before enabling this option.
Reset Ratio (RTIO) — This configuration is used when
RS.CF is set to 1 or 2. For every degree that the controlling
temperature (space/return) falls below the occupied cooling set
point (OCSP), the calculated value of the supply air reset will
rise by the number of degrees as specified by this parameter.
Reset Limit (LIMT) — This configuration is used when
RS.CF is set to 1 or 2. This configuration places a clamp on the
amount of supply air reset that can be applied.
EDT 4-20 mA Reset Input (RES.S) — This configuration is
automatically enabled when Configuration → EDT.R →
RS.CF is set to 3 (third party reset).
COOLING CONFIGURATION — Relevant configurations for
mechanical cooling are located at the local display under
Configuration → COOL. See Table 37.
Capacity Threshold Adjust (Z.GN) — This configuration is
used for units using the “SumZ” algorithm for cooling capacity
control (Configuration → UNIT → C.TYP = 1, 2, 3 or 5). The
configuration affects the cycling rate of the cooling stages by
raising or lowering the threshold that demand must build to in
order to add or subtract a stage of cooling.
Normally this configuration should not require any tuning or
adjustment. If there is an application where the unit may be sig-
nificantly oversized and there are indications of high compres-
sor cycles then the Capacity Threshold Adjust (Z.GN) can be
used to adjust the overall logic gain. Normally this is set to 1.0,
but it can be adjusted from 0.5 to 4.0. As the value of Z.GN is
increased, the cycling of cooling stages will be slowed.
Compressor Lockout Temperature (MC.LO) — This config-
uration is the outdoor air temperature setting below which
mechanical cooling is locked out.
Lead/Lag Operation? (L.L.EN) — This configuration allows
for lead/lag compressor operation for the unit. If this configura-
tion is set to Yes, every time cooling capacity drops to 0%, on
the next call for cooling, the control will start up the first
compressor on the circuit which did not start the previous
cooling cycle. If set to No, circuit A will always start first.
Motormaster Control? (M.M.) — The condenser head pressure
control for the unit is managed directly by the ComfortLink™
controls. There is no physical motormaster device in the unit.
This configuration allows the head pressure control sequence to
permit additional cycling control of the condenser fans. Setting
this configuration to YES permits mechanical cooling operation
down to 0° F (–18 C) outdoor temperature. If this configuration
is set to NO, the mechanical cooling system is not suited for
operation below 35 F (1.8 C) outdoor temperature.
Head Pressure Set Point (HPSP) — This is the head pressure
set point used by the ComfortLink controls during condenser
fan, head pressure control.
Enable Compressor A1 (A1.EN) — This configuration is
used to disable the A1 compressor in case of failure.
Enable Compressor A2 (A2.EN) — This configuration is
used to disable the A2 compressor in case of failure.
Enable Compressor B1 (B1.EN) — This configuration is
used to disable the B1 compressor in case of failure.
Enable Compressor B2 (B2.EN) — This configuration is
used to disable the B2 compressor in case of failure.
CSB A1 Feedback Alarm (CS.A1) — This configuration is
used to enable or disable the compressor A1 feedback alarm
(105 ton size units only). This configuration must be enabled at
all times for 105 ton units.
ITEM EXPANSION RANGE
CCN
POINT
DEFAULTS
UNIT UNIT CONFIGURATION
SIZE Unit Size (30-105) 30 - 105 UNITSIZE *
50.HZ 50 Hertz Unit ? Yes/No UNIT_HZ *