Roberts Gorden Combat HF 30 v4, Инструкция по установке, пусконаладке, обслуживанию и эксплуатации

Страница: 21 / 76

Page 19
CABINET HEATER
Fig. 2.4 Motor Starter (Models 040 - 0100) and Thermal Overload
(Models 060- 0100 only)
2.5 Motor Starter and Thermal Overload
On belt driven fan models the motor is controlled by a direct on line contactor starter fitted with thermal overload
protection. If the thermal overload should operate the main fan will not run. To reset, press in the reset button on the
overload unit (see Fig. 2.4). Note: For models fitted with a 5.5kW motor or larger, then the direct on line starter will be
replaced by an automatic start delta starter - see Fig. 6.14).
The overload should be set to indicate approximately 0.2 amps above the normal running current of the heater (see
Table 2.1 Technical Data).
Single phase direct drive fans are controlled directly by the fan thermostat and three phase direct drive fans are
controlled by a direct on line contactor starter, but using the motors built in thermal overload protection to operate the
contactor coil. On direct drive fan models the thermal overload is built into the motor and is an automatic reset device,
connected as shown in the Wiring Diagrams, Section 6.
2.6 Burners
For details of the Packaged Burners see the Manufacturer’s Instructions and the Data Tables in Section 2.1.
When reading the Data Tables ensure that the correct table for the burner and gas valve installed is being used. The
Data Tables are listed under a burner reference letter which can be found on the heater data plate.
2.7 Gas Valves Used with All Burners
2.7.1 Dungs Combination Gas Valves
The Combination Valve features as shown in Fig. 2.6.
All model 015 to 030 gas fired burners operate as direct main flame ignition and have no separate start gas train. All
other models operate with a first stage start gas flame supplied from a start gas train containing a start gas pressure
regulator and two safety shut off valves, for all gas types.
The main gas is released at the second stage and the combination main gas valve block contains a main burner
pressure regulator and two safety shut off valves, for all gas types.