Bird Technologies 8890-400 Series - Manuale (Pagina 19)

Chapter 3
Installation
Power and
Utility
Requirements
The Series 8890-400 Wattmeters are fully self-contained. No
additional equipment or outside power source is needed, un-
less the load is equipped with an optional BA-310 blower as-
sembly. If it is, either 115 V, 50/60 Hz or 230 V, 50/60 Hz ac
power is required.
Environmental
Requirements
Although Series 8890-400 Wattmeters are ruggedly built
and have no moving parts, a dust and vibration free dry en-
vironment is preferred. For the Wattmeter to function ac-
cording to its specifications it is important that:
1. The ambient temperature remains within the
range of +10°C to +40°C (50°F to +104°F)
2. Access to air is not impeded. It is recommended
that a clear space of at least 12 inches (30 cm)
be allowed around the load.
Because the wattmeter absorbs and dissipates, as heat, all
of the RF power it receives, no harmful RF radiation is re-
leased into the environment.
Tools
Required
s Screwdriver
s Box wrenches — needed for changing connec-
tors, changing the coolant, etc.
s Ohmmeter — For checking the resistor. An
ohmmeter with an accuracy of one percent or
better at 50 ohms is suggested. A simple volt-
ohm meter will suffice for checking the blower
assembly and thermoswitch.
Mounting The Series 8890-400 Termaline Wattmeters are equipped
for either fixed installations or portable use. There are
mounting brackets on the front and rear faces of the unit.
The load may stand free or be attached to a bench, etc., by
means of four fasteners. Four 3/8 inch (9.53 mm) mounting
slots, to be used with appropriate screw sets up to 3/8 inch
diameter, are arranged in a 4-1/2 inch x 20-23/32 inch rec-
tangle (114.3 x 526.3 mm).
Coupling Kits Models 8891-400A, 8891-415B, and 8891-420B: The RF con-
nector section has bolted flanges that are swivel type. It is
inserted into the existing transmission line using a coupling
kit, P/N 4600-020.
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