UFC 3-535-01
17 November 2005
Table 15-2. 5-Step 6.6-ampere Circuit (FAA Class 1, Style 2)
Brightness Step
Nominal Current
Allowable Tolerance
(amperes)
Current (amperes)
5
6.6
6.40 - 6.70
4
5.2
5.04 - 5.36
3
4.1
3.98 - 4.22
2
3.4
3.30 - 3.50
1
2.8
2.72 - 2.88
Table 15-3. 3-Step 6.6-ampere Circuit (FAA Class 1, Style 1)
Brightness Step
Nominal Current
Allowable Tolerance
(amperes)
Current (amperes)
3
6.6
6.40 - 6.70
2
5.5
5.33 - 5.67
1
4.8
4.66 - 4.94
15-5.7
CCRs larger than 30KW are rated at 20 amperes output current, while
smaller CCRs are rated at 6.6 amperes output current. 15KW through 30KW CCRs may
be selected for either 20 or 6.6 amperes output current. Intensity steps are either 5-step
or 3-step.
15-6
SIZING THE REGULATOR WHEN REIL ARE CONNECTED TO THE
CIRCUIT
In its Advisory Circulars, the FAA does not address the load imposed on the CCRs by
the constant current to constant voltage adapters necessary for REIL operation, or the
REIL that are connected into series circuits. With the constant flashing of the lights and
the resulting discharging of the capacitor, the REIL place a very short, but heavy,
pulsing load on the regulator. Occasionally, this type of pulsing load results in pulsation
of the illumination of the steady burning lights on the circuit. This "reflective" pulsation
depends on the characteristics of the regulator powering the circuit and on the
characteristics of the REIL connected into the circuit. The design engineer needs to
ascertain from the regulator manufacturer which type of CCR will handle the overall
series circuit load with the addition of the REIL pulse-type load without adverse effect. It
has been shown that the problem will be minimized if the REIL are connected into
series circuits that have primarily incandescent loads and the circuit load approaches
the capacity of the regulator.
15-6.1
The actual regulator capacity needed to operate the REIL properly is
much greater than the rated load indicated in the typical product literature. Usually the
average power requirement is provided; however, the regulator has to accommodate
the instantaneous, or pulsing, load to provide the flashing characteristics of the REIL.
That REIL may be rated to require only 400 watts to operate, but may actually require
up to 4 kilowatts of regulator capacity to meet the pulsing load requirements when also
including the impact of the series circuit adapters between the series circuit and the
REIL. The series circuit adapters convert 6.6 amps to 120 volts for REIL operation, and
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