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VP-X Installation and Operating Manual
Rev. D (August 5, 2020)
• Max Amps:
The maximum current load that a pin is capable of
handling. A load drawing more than this amount of current will fault
(i.e., turn off) the load.
• Actual Amps:
The actual current drawn by a device. It is
recommended you measure the ACTUAL current draw of each
device prior to installation in the aircraft using an ammeter. The total
actual current draw should not exceed 60 Amps.
•
Circuit Breaker:
The maximum current allowed for that pin. You
can enter any value between 1 and the limit of that pin in increments
of 1A. This value is equivalent to a circuit breaker or fuse. If a load
draws more than the Circuit Breaker value, that circuit will fault. If
too large of a breaker value is used, then the wire may overheat or
fail. If too small a value is used, then the device may fault the circuit
because it draws too much current.
•
Switch:
Enter the number of the switch input (switch input 1 through
10) you want to control this pin, or set to ‘always on’ or ‘always off’.
Each switch input is labeled 1 through 10. You can assign multiple
devices to a single switch, and conversely, a switch can control
multiple devices. If you set the circuit to ‘always on’, it will be on
anytime the VP-X is powered (i.e. the master switch is on). Multiple
pins can be assigned to a single switch. Switch inputs are on J2, pins
1 through 10. You don’t have to use all of the switch inputs.
• Current Fault:
The pin can be configured to detect a “current
fault” or open circuit. When a circuit with this feature enabled is
turned on and does not draw any current for 3 seconds, the circuit
is faulted. You can use this to detect burned out lights, faulty boost
pump, failed avionics fan, or inop heated pitot tube for example. The
minimum detectable current is about 100ma, so this should be used
on devices like lights, strobes and loads that draw at least 100ma of
current.
• AWG:
The size of the wire based on the industry standard American
Wire Gauge. This is the minimum recommended size wire for this
circuit. Do not use a smaller gauge (bigger gauge number) wire.
4.13a What if I run out of power pins?
There are several options if you have more electrical devices than power
pins on the VP-X. Evaluate each of the following and choose the one that
makes the most sense for you:
1. Combine several devices together on a power pin. Typically these
are low-current devices that are all switched on and off together.
Since the circuit protection is designed to protect the wire, you can
group items as long as the CB value does not exceed the specs for
the smallest wire. For example, an XM receiver and CO detector
could be combined on a circuit and set to 2A fuse. Downside is if one
device faults, then both devices lose power.
2. Create an auxiliary bus by running an 18 gauge wire from one of the
10A power pins (set CB to 10A) to a fuse block with 6 or so fuse
holders. From each fused tab, run a
wire to the device. Do not install fuses
rated at more than 3A, and ensure the
total load does not exceed about 8A.
Often devices that need a 1 to 3 amp
fuse draw less than half an amp, so
you can easily put 6 or 8 devices on a
fuse block. When an individual fuse
blows, the others are unaffected. All
devices will be turned on and off
together.
3. If you’re wiring backup circuits,
you may already have a fuse block
designed to power the backup circuits. Run devices off this fuse
block, through external switches.
4. Contact us at info@verticalpower.com for assistance.
4.13b What if I run out of switch inputs?
If you need more than 10 switches (plus the master, trim, and flap switches),
you can wire the switch in series between the VP-X and the device. We
recommend using circuits with low-current loads like cabin lights, panel lights,
or other similar devices. Doing so allows you to use the same style of switch
for all devices (you don’t have to install a special high-current switch). Wire
as shown in the diagram below:
VP-X
Device
SPST
Switch
Unlike the other switches, this switch must be rated to carry the current load
of the device.
Fuse
Fuse
Fuse
Fuse
Fuse
Fuse
VP-X
10A
