Camus Hydronics DRH300, Инструкция по установке, эксплуатации и обслуживанию

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21
Dynaforce®
Model
Voltage
Requirement
Maximum
Over Current
Protection
Full Load
Amps
[Amperes] [Amperes]
1200 -
2500
460VAC, 60Hz, 3
Phase
10
2.1
3000 -
4000
5.3
4500 -
5000
6.8
The combustion air fan motor operates on 230 VAC, 3 phase,
60 Hz on models DR1200 - 5000. Three phase voltage is
generated by the VFD and supplied directly to the fan motor on
models 1200 - 5000. Refer to Table 10 for appropriate supply
voltage to the appliance. The appliance, when installed, must
be electrically grounded in accordance with the requirements
of the authority having jurisdiction or in the absence of such
requirements, with the latest edition of the National Electrical
Code ANSI/NFPA No. 70. When the unit is installed in Canada,
it must conform to the Canadian Electrical Code, C22.1, Part 1
and/or local Electrical Codes.
•
All wiring between the appliance and field installed devices
shall be made with wire having minimum 220ºF (105ºC)
rating.
•
Line voltage wire external to the appliance must be
enclosed in approved conduit or approved metal clad
cable.
•
The pump must run continuously when appliance is firing.
•
To avoid serious damage, DO NOT ENERGIZE the
appliance until the system is full of water. Ensure that all
air is removed from the pump housing and piping before
beginning initial operation. Serious damage may result if
the appliance is operated without proper flow.
•
Provide the appliance with proper overload protection.
5.2 VARIABLE FREQUENCY DRIVE (DR1200 –
5000)
This appliance uses a VFD which provides power to the
combustion fan. The fan motor operates on 230VAC 3 phase
power. This three phase voltage is generated by the VFD and
supplied directly to the fan motor. The VFD receives a 4-20mA
modulating signal from the SOLA to vary the frequency of the
voltage supplied to the fan motor from 20 Hz up to 60 Hz. This
varies the output of the combustion air fan from 20% up to
100% of capacity corresponding to the same variation in
burner input. Once the self checks are completed by the
SOLA, the VFD is provided with a signal to operate at soft start
level for initial burner ignition. After main burner ignition is
established, the modulating signal is generated by the VFD to
vary fan speed based on desired water temperature set point.
CAUTION
The voltage output from the variable frequency drive to the
combustion air fan is 230VAC, 3 Phase. AVOID contact
with high voltage wiring
5.3 DIFFRENTIAL AIR PRESSURE SWITCH
Models 300 to 1000 use a fan speed sensing line in the PWM
control to prove air flow. A normally open differential air
pressure switch is used to prove operation of the combustion
air fan on the DR1200 – 5000. The pressure switch sensing
points are installed at the fan outlet where air moves into the
inlet of the burner. One point measures total pressure (+air)
and is connected to a pitot tube facing the flow from the fan
paddle wheel. The other point measures static pressure.
Differential pressure at the switch will be affected by
blockages at the fan inlet or at the flue discharge. A
minimum differential pressure across the sensing points of
the pressure switch proves operation of the combustion air
fan. This is set in the factory and may be adjusted for field
conditions. The diagnostics display will exhibit a status of
an open Interrupted Air Switch (ILK Off) when the
differential pressure switch detects a sustained low air
condition. This condition could be caused by a number of
factors including:
•
Sensing line broken or loose fitting.
•
Dirty filter or blocked vent.
•
Steady high wind condition exceeding 40 MPH.
•
Incorrectly set switch.
•
Missing bleed restrictor on total pressure side air
line.
5.4 BLOCKED FLUE SWITCH
All models use a normally closed blocked flue switch to
shut down the appliance under the following conditions:
1) Air intake 50% blocked
2) Vent outlet 80% blocked
5.5 DIFFERENTIAL GAS AND LOW GAS
PRESSURE SWITCHES
A manual reset differential gas pressure switch is standard
on DR3000 – 5000 and available as an option on DR300 -
2500. If differential gas pressure exceeds the maximum
setting of the pressure switch, the appliance will shut down
and an open gas pressure switch will be shown on the
display. A low gas pressure switch is standard and
monitors the minimum incoming gas supply pressure
supplied to the gas train. If gas pressure falls below the
minimum setting of the pressure switch, the appliance will
shut down and an open gas pressure switch will be shown
on the display.
5.6 HIGH LIMIT
A high limit aqua-stat control is located at the back of the
appliance and the control bulb is installed in a dry well in
the heat exchanger header outlet. The setting of this
control limits maximum discharge water temperature. A
manual reset high limit will have a red reset button which
must be pushed whenever water temperature has
exceeded the set point of the manual reset limit. The
temperature of the water in the heat exchanger must drop
a minimum of 15°F (8.3°C) below the setting of the high
limit control before the reset function can be activated.
Whenever an appliance is supplied with both an auto reset
and manual reset high limit always set the auto reset limit
10
ºF (5.5°C) below the manual reset limit to prevent
nuisance tripping