IOM SyScroll 140 360 Air EVO 361549

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English
8 - Technical Data (continued)
By default, VFD is programmed to operate at [Auto On]
mode. Customer can change the SETPOINT by following
the below mentioned instructions:
Press [Main Menu] to select the Main Menu mode. The
below read out appears on the display. The bottom section
on the display shows a list of parameter groups , select
Parameter 20-xx Drive Closed Loop which can be selected
by toggling the [▲] and [▼] keys and then select 20-21
Setpoint 1 and change the value of default setpoint by [▲]
and [▼] keys.
IMAGE 04: Control logic
IMPORTANT! The differential pressure transducer,
the pressure transducers and the By-pass valve are
supplied loose at customer charge. Systemair provides
only indications for the plant design with respect to the
minimum water flow on the primary heat exchanger.
• Variable primary flow (Constant ΔT)
1. Application
This option is to provide a flow rate in order to maintain
constant the delta between the inlet and outlet temperatures
of the chiller. This option is to be implemented on the water
loops with two or three way valves and can deliver higher
energy saving compared to constant DP in the majority of
the comfort applications.
2. Description
With this option, SYSCROLL 140-360 AIR EVO chillers
will be equipped with a hydraulic module driven by a
frequency drive, the modulation of the pump speed is
to ensure that the DT across the water loop is constant.
At minimum partial loads, the minimum flow across the
chiller evaporator should be ensured or a by-pass valve
should be installed to prevent the evaporator from low
flow, which otherwise is very critical to the chiller system.
IMAGE 05: Constant ∆T Control diagram
Note: In two-pump configuration, there is an alternation of
the pump operation for every 12 hrs.
Note: For the electrical connection of temperature
transducers and By-pass valve, refer to electrical drawings
of the hydraulic module.
3. Operation
The Entering and leaving temperatures across the chiller
are measured directly by the frequency drive controller,
through the factory supplied temperature transmitters. A
Delta T set point will be preset on the unit controller of the
frequency drive (∆T=5 by default).
IMAGE 06: Control logic
By default, VFD is programmed to operate at [Auto On]
mode. Customer can change the SETPOINT by following
the below mentioned instructions:
Press [Main Menu] to select the Main Menu mode. The
below read out appears on the display. The bottom section
on the display shows a list of parameter groups , select
Parameter 20-xx Drive Closed Loop which can be selected
by toggling the [▲] and [▼] keys and then select 20-21
Setpoint 1 and change the value of the default setpoint of
‘5’ by [▲] and [▼] keys.
IMPORTANT! The temperature transmitters and By-pass
valve are supplied loose at customer charge. Systemair
provides only indications for the plant design with respect
to the minimum water flow on the primary heat exchanger.