Calrec Hydra2, Installation Manual

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CALREC
Putting Sound in the Picture
103
FIGURE 2 - HYDRA2 MODULAR I/O SPECIFICATIONS
Powering
The 3U Stagebox I/O Rack has two pluggable AC-48V DC power modules fitted in the back of
the unit. Each power module has four retaining screws, the screws can be released or tightened
by hand or with an appropriate sized cross head or straight blade driver. Although the rack will
operate with one inlet supply we recommend both inlets are powered. This will ensure continued
operation should a PSU or AC source fail. When both power modules have an AC supply the load
is shared.
The operating AC supply voltage is 100V - 240V +/-10%.
The inrush current to each power module is actively limited. At 115V the maximum current is 6.5A
and at 230V the maximum current is 13A. This reduces the chance of a nuisance trip or fuse
blow from power ups, dips and interruptions.
The power requirement (VA) depends on the type and quantity of I/O modules fitted (up to 20
maximum). The highest it can be is 200W. The RMS quiescent current figures for a given input
voltage are available for all configurations of I/O rack.
Power Factor
The internal power supplies fitted have active power factor correction to ensure the harmonics are
within the limits of the standard EN61000-3-2. A good power factor brings the apparent power
down closer to the real power and is more efficient. It also provides a more sinusoidal current flow
with a much reduced peak magnitude in the AC distribution cables, this produces much less low
frequency noise from the cables that could otherwise couple into sensitive signal paths.
Heat Output and Efficiency
The Heat output from the rack depends on the type and quantity of I/O modules fitted. The
highest it can be is 185W. A good rule of thumb for these units is 0.9 x VA (RMS).
The PSU efficiency is dependant on loading. The efficiency improves with more I/O modules
fitted. Most configurations will be between 75 - 88%.
Cooling
The 3U rack keeps its operating temperature under control with fan assistance. Each of the
two power modules has an 80mm fan mounted externally on its rear panel. The speed of
the fans is under internal temperature control. Racks equipped with Mic Input and/or AES
modules are lower power so the fans will run slow for use in studios etc. Racks equipped with
higher density Line In/Out and/or SDI modules are higher power so the fans will run faster
as required. This configuration of rack is intended for use where fan noise isn’t an issue. The
rack has been designed so that if an AC source or a PSU should fail, both fans will continue
to run normally so the cooling is maintained. The fans are speed monitored so if one goes too
slow or stops a warning is given. The air intake is at the underside of the rack but the design
of the rack allows air in from the sides to the same area when mounted against a flat surface.
It is essential that the rack is not mounted on anything like carpet or soft furnishings as this
will restrict or block the air intake. The air outtake is directly from the fans on the rear of the
unit. At least 50mm (2”) clearance must be maintained for the side and rear vents. The rack
may be mounted in an open bay providing the ambient air temperature is within limits (see
below). The rack may also be housed in any air conditioned bay.
Operating Ambient Air Temperature 0°C - 35°C
Relative Humidity 5% – 90% Non-condensing