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Safety Precautions Safety Precautions The following are general safety precautions that are not necessarily related to any specific part or procedure, and do not necessarily appear elsewhere in this publication. These precautions must be thoroughly understood and apply to all phases of operation and maintenance. Keep Away From Live Circuits Operating Personnel must at all times observe general safety precautions.
Termaline® Load Resistor Safety Symbols Warnings call attention to a procedure which, if not correctly performed, could result in personal injury. Cautions call attention to a procedure which, if not correctly performed, could result in damage to the instrument. This symbol indicates that a shock hazard exists if the precautions in the instruction manual are not followed.
Safety Precautions Warning Statements The following safety warnings appear in the text where there is danger to operating and maintenance personnel and are repeated here for emphasis. The load weighs 142 lb. (64.4 kg) lbs, do not attempt to lift alone. Two or more people are required to lift the load.
RF power to less than 2,500 W. See page 9 If installed, connect optional interlock before applying RF power. See page 9 Use only Bird coolant, P/N 5-1070, to prevent damage to the load. See page 14...
Safety Precautions Safety Statements USAGE ANY USE OF THIS INSTRUMENT IN A MANNER NOT SPECIFIED BY THE MANUFACTURER MAY IMPAIR THE INSTRUMENT’S SAFETY PROTECTION. EL USO DE ESTE INSTRUMENTO DE MANERA NO ESPECIFICADA POR EL FABRICANTE, PUEDE ANULAR LA PROTECCIÓN DE SEGURIDAD DEL INSTRUMENTO. BENUTZUNG WIRD DAS GERÄT AUF ANDERE WEISE VERWENDET ALS VOM HERSTELLER BESCHRIEBEN, KANN DIE GERÄTESICHERHEIT BEEINTRÄCHTIGT WERDEN.
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Termaline® Load Resistor SERVICE SERVICING INSTRUCTIONS ARE FOR USE BY SERVICE - TRAINED PERSONNEL ONLY. TO AVOID DANGEROUS ELECTRIC SHOCK, DO NOT PERFORM ANY SERVICING UNLESS QUALIFIED TO DO SERVICIO LAS INSTRUCCIONES DE SERVICIO SON PARA USO EXCLUSIVO DEL PERSONAL DE SERVICIO CAPACITADO.
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Safety Precautions CONNECT INTERLOCK TO TRANSMITTER/GENERATOR/AMPLIFIER BEFORE OPERATING. BRANCHER LE VERROUILLAGE À L’ÉMETTEUR/GÉNÉRATEUR/AMPLIFICATEUR AVANT EMPLOI. CONECTE EL INTERBLOQUEO AL TRANSMISOR/GENERADOR/AMPLIFICADOR ANTES DE LA OPERACION. VOR INBETRIEBNAHME VERRIEGELUNG AM SENDER/GENERATOR/VERSTÄRKER ANSCHLIESSEN. PRIMA DI METTERE IN FUNZIONE L’APPARECCHIO, COLLEGARE IL DISPOSITIVO DI BLOCCO AL TRASMETTITORE/GENERATORE/AMPLIFICATORE.
When inquiring about updates to this manual refer to the part number and revision on the title page. Chapter Layout Introduction — Describes the features of the Bird Termaline RF Load Resistor lists equipment supplied and optional equipment, and provides power-up instructions. Theory of Operation —...
Chapter 1 Introduction Bird 8930 Series Loads are general purpose, 50 ohm, coaxial RF transmission line terminations, useful as standby reject loads for single or double sideband transmitters. They provide accurate, dependable, and low reflection line terminations over a frequency range of DC – 1000 MHz. Up to 10,000 watts can be dissipated.
Theory of Operation Load Resistor Bird 8930 Loads consist of a thin-film-on-ceramic resistor immersed in a dielectric coolant. The resistor, individually selected for its accuracy, is enclosed in a special housing. When surrounded by the coolant, this produces a uniform, practically reflection-less line termination over the specified frequencies.
If the shipping container is not damaged, unpack the unit. Save shipping materials for repackaging. 2. Inspect unit for visual signs of damage. If there is damage, immediately notify the shipping carrier and Bird Technologies. Site and Shelter Requirements Do not block airflow. The air intake vent on the bottom of the load must not be obstructed.
Bird 8930 Loads are intended for stationary or fixed use. The mounting brackets on front and rear faces have four mounting holes arranged in a 7" x 27 "...
Installation Thermoswitch Bird 8930 Loads can be equipped with an optional interlock thermoswitch, P/N 8890-017. It is normally closed, opening at 226 °C (439 °F), with a rating of 10A @ 120VAC and 5A @ 230VAC. A control thermoswitch, P/N 8892-333, is used to control the blower assembly. It is normally open, closing at 60 °C (140 °F), with a rating of 10A @ 120VAC and 5A @ 230VAC.
Termaline® Load Resistor 9. Remove the shipping plug. 10. Verify the O-Ring is installed on the vent plug. 11. Install the vent plug. Interlock Connection If installed, connect the optional interlock thermoswitch to the interlock as follows (see Figure 2 If installed, connect optional interlock before applying RF power.
Installation AC Power Connection Turn off AC power and RF power when attaching the power cable. Check the local electrical code for proper ac hookup prior to operation of the unit. Make sure the neutral or return hookup is only used for that purpose. The AC power supply required for this unit is 115/230 V, depending on the model, @ 50/60 Hz, 1.
Termaline® Load Resistor The swivel flange on the load makes connection independent of the orientation of the fixed flange on the coaxial input outer conductor. Insert the bolt sets and tighten evenly all around to transmission line manufacturer’s recommended torque.
Blower Controls Bird 8930 Loads are equipped with a control switch and indicator light on the front of the blower, underneath the RF connector. The switch is labeled “MANUAL/AUTOMATIC”. When the switch is set to MANUAL, the fans will run continuously.
Termaline® Load Resistor Emergency Shutdown Turn off RF power at the source. If the interlock thermoswitch is properly connected, RF power will be automatically turned off when the coolant temperature reaches an unsafe level.
Chapter 5 Maintenance Disconnect the unit from all power sources before servicing. The unit may be energized from multiple sources. The potential for electric shock exists. Never attempt to connect or disconnect RF equipment from the transmission line while RF power is being applied.
Termaline® Load Resistor Routine Maintenance shows the location of components which may be referred to in this section. Figure 5 Figure 5 Maintenance and Repair Locations CLAMPING BAND AND O-RING “QC” CONNECTOR SCREWS FUSE SIDE BAFFLE DRAWER SCREWS MANUAL AC ON FAN GRILL AUTOMATIC Inspect the Load...
Maintenance Clean the Blower Assembly The intake grills, fans, and inside of the baffles should be wiped free of dust and dirt when necessary. When the blower assembly is installed, it will be necessary to partially disassemble the blower to clean the load’s radiator fins.
5 inches (125 mm) below the top surface of the resistor assembly mounting ring, at ambient temperature. Use only Bird coolant, P/N 5-1070, to prevent damage to the load. 3. Add coolant if necessary. 4. Install the load resistor (See to "Load Resistor Replacement"...
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Maintenance Figure 6 Measuring DC Resistance...
Figure 5 on page 12 RF Connector Replacement The Model 8931, only, has a Bird “QC” connector which allows easy changing of the RF connector. This does not disturb the coolant seal or affect the electrical continuity of the load. To change the connector: ...
Maintenance The O-ring should be free of twists and positioned evenly around the flange of the resistor housing. If the O-ring shows signs of deterioration (e.g. is no longer pliable or has surface cracks) replace it. 10. Inspect the coolant, see "Inspect the Coolant"...
"Specifications" on page 21 4. Press the drawer into the AC module until it locks into place. 5. If the fans still do not run or if the fuse burns out again, return the unit to Bird for service. Figure 7...
Maintenance Fan Replacement When ordering a replacement fan, be sure to specify the model, the fan part number, AC voltage, and fan position. The fan will be provided with lugs and leads of the right length for direct attachment to the terminal block. Different fans are used in the 115V and 230V loads.
Any maintenance or service procedure beyond the scope of those in this chapter should be referred to a qualified service center. If the unit needs to be returned for any reason, request an Return Material Authorization (RMA) through the Bird Technologies website. All instruments returned must be shipped prepaid and to the attention of the RMA number.
Maintenance AC Line Supply Cable 115 V 8950A023-1 230 V 8950A023-2 Available “QC” Type Connectors Connector Part Number BNC-Female 4240-125 BNC-Male 4240-132 C-Female 4240-100 C-Male 4240-110 HN-Female 4240-268 HN-Male 4240-278 4240-031 LC-Female LC-Male 4240-025 Open Term. # 10-32 Nut 4240-080 LT-Female 4240-018 LT-Male...
Limited Warranty All products manufactured by Seller are warranted to be free from defects in material and workmanship for a period of one (1) year, unless otherwise specified, from date of shipment and to conform to applicable specifications, drawings, blueprints and/or samples. Seller’s sole obligation under these warranties shall be to issue credit, repair or replace any item or part thereof which is proved to be other than as warranted;...
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