Secondary Power Distribution Demonstration, Part 1: Overview

Welcome to AMETEK PDS. Today I am going to give an

overview

of our

secondary

power

distribution

unit. This will be one of a series of videos in which we walk through the SPDU and show the various features and capabilities of the unit while installing it on an aircraft for

secondary

power

distribution

. This is a 27 channel secondary power distribution unit. It has a 28 volt main power supply, so there are up to 27 individual solid state power controllers. You can communicate digitally with this device either using the CAN or ARINC 429 bus, depending on what you decide to use, and it also has a maintenance connector here specifically for uploading and downloading configuration tables, which will be a whole topic of another video. later, but it shows you the configurability and flexibility of the unit.

On this side of the unit, these are all output channels. These are the low current output channels. So it channels up to 7.5 to 10 A output. While these are high current output channels where you can have up to 30 A outputs on a single SSPC channel. This

part

icular unit is a single channel unit, so it has one main processor but has a lot of built-in redundancy. You have redundant power supplies, redundant communications, redundant communications up to the SSPC, so there are a lot of safety factors there, there are a lot of CRC32 integrity checks to ensure that the data is good, the communication is good and then what we do is we connect to this computer, and today it is connected to ethernet and CAN.

So we use CAN to talk to it and turn loads on and off and we use Ethernet to upload and download configuration tables or change the trip configuration of an SSPC. This

part

icular unit comes with a ton of discrete I/Os that are completely flexible. So not only do you need to turn on and off a load with an ARINC or CAN tag, you can also selectively assign any of these spare discretes so that when you turn on the discrete you can turn on a load, you can turn off a load, it's all configurable in the configuration table, and that will be something we will talk about later.

The unit handles up to 144A output and is environmentally sealed. It has an O-ring here. The chassis and the mass of the electronics are the same. All return current usually passes through the fuselage, but you can attach the feet using the feet or you can attach them using a ground strap, such as braid, to a local point on the aircraft. Each unit on the aircraft has its own individual address and can support up to 16 units, 16 different locations on the aircraft, so each is individually addressed by addresses and parity IDs. Once the ID is known, that's how the plane's multifunction display knows who to talk to or who to turn things on and off.

In the following videos, what we will do is control many of these loads; This is just a visual representation of the loads turning on and off; I will show you many different features. What this actually does is completely replace an airplane's circuit breaker panel. Also replaces any type of relays where you need to be downstream. It has no moving parts, it is completely solid state. These are solid-state MOSFET-based and in-channel MOSFET-based switches. What that does is give you responsiveness, much better than a thermal switch, probably 10 to 100 times faster. What this means is better cable protection, including arc fault protection, and we'll demonstrate a lot of that in the following videos.

This was a quick

overview

of our 27 channel SPDU. Feel free to explore our other related videos that explore the specific features and capabilities of AMETEK power distribution. Thanks for watching.