L-1011 Trainer Installation: AC an DC Standby Power from Battery

L-1011 Trainer: AC and DC STBY Power from Battery

Finished the L-1011 AC Standby (STBY) and DC STBY power fail-over to the on-board Battery yesterday evening. On the actual aircraft, once transferred to Battery power, the standby buses are alive for about 30 minutes before the Battery is depleted.

Normally, the DC STBY bus receives powered from the DC Essential bus and the AC STBY bus is powered by the AC Essential bus. The AC and DC STBY bus are the last resort to keep the aircraft operational in case of a complete loss of primary electrical systems. If the respective Essential power busses fail, the STBY busses are switched to the on-board Battery. AC power is created form the on-board Battery via a DC to 115V/400Hz Inverter. Watch the short demonstration video below and you will see the system in action.

L-1011 Trainer Installation: Flight Station Bus Failure

L-1011 Trainer: Flight Station Bus Failure 

The FLT STA BUS FAIL lights are located on the Electrical System panel of the L-1011 S/O station. The lights illuminate amber when power is lost to the Flight Station Bus segment of the respective AC Load Bus.

The ELECTRICAL SYSTEM annunciator also illuminates on the Pilot's Annunciator Panel, however, this part has not yet been implemented. Below is a short video that demonstrates the Flight Station Bus failure and how it occurs independent form the Load Bus.

L-1011 Trainer Installation: Simulator Power Controls

L-1011 Trainer Installation - Power  Controls

The last few days we have been working on some of the less exciting, yet very important, components such as the simulator power control. You can see the primary power elements in the image above. The power controls from left to right are:

1. Main Power - this controls power to the flight simulator. The rocker switch is not only an ON-OFF switch but also a breaker that will drip at 15A. 
2. Computer/Visual - this switch controls the power ON-OFF state for the computers and video projects that are part of the L-1011 simulator. 
3. External Power - simulates external power being supplied to the aircraft. This external power would be either power supplied from a source at the gate or from a start cart. External power to the aircraft would be supplied via a ground connected cable. Switching this rocker switch to ON will illuminate the green AVAIL light on the Second Officer's console. 
4. Cooling System - activates the cooling system for the flight simulator. 

Below is an image of the entire control unit that houses the power controls and the computers.

L-1011 Trainer - Power Control and Computer Rack

L-1011 Trainer Installation: 400Hz Power Distribution

L-1011 Trainer Installation: 400Hz Power Distribution

Today we put about 75% of the 400Hz power distribution in place. For the simulator we are really dealing with 3 different power sources: a) the 24V DC power system, b) 120V 60Hz AC power and c) 115V 400Hz AC power. Creating (a) and (b) was easy, however, as you saw in the previous posting, the 400Hz power required a special inverter that converts 60Hz power to 400Hz power. We are actually using the system we built for the 120V 60Hz power to drive the 400Hz power system. In other words, the power sense modules on the 60Hz side instruct bus segments on the 400Hz side to power on and off with respective relays.

To keep things a bit easier to identify we are using blue cables for the 400Hz system. The image below shows the current build state of the 400Hz system.

L-1011 Trainer - 400Hz Bus System Build out

By the way, the image shows some nifty new DIN rail mounts (the silver rack mounts) that Jim Blasco custom built for the project. They are really awesome and come at quite a cost saving to the project. Thank You Jim! Eventually all the cables will be dressed out once the system is fully built and it will certainly look a lot less like a rats nest :)

L-1011 Power Distribution System - Trainer Installation

L-1011 Trainer Installation: 400Hz Power in the Sim

115V AC 400Hz Power Inverter

Today we finally powered up the 115V AC 400Hz inverter for the Lockheed L-1011 trainer. Thanks to Richard Grigg and the engineers from Paul Wiley Electrical who worked late into the evening yesterday to establish the power feed from the main board to the sim room. The device will produce 5000VA on a single phase and will be able to meet all the needs for 400Hz avionics power that we have in the sim and then some more. There was an option to run it as 10KVA device, but we chose not to install it that way. Here are some more details on the unit:

High Power AC 400Hz Military APU 3 Three Phase Inverter 10 KVA output power. Manufactured by Transistor Devices, for transport (Lockheed C130) Auxiliary Power Unit. Input voltage is 208 three phase 50/60 Hz, Output is 200/115 (phase to phase/phase to neutral) VAC at 28 amps/leg, Model numbers are ESU127/A Power supply, and ECU-128/A for the static inverter modules. The inverter is built up from three modules. The thin one on the left is the redundant AC input module that does power factor correction. It then sends 350-450 VDC to the power supply inverter module on the right. Inside the right module a switch mode power supply takes the PFC output voltage and generates +/-200VDC and sends it off to the three phase inverter. The inverter then chops up the DC into three phase 115/200 Wye configuration (with neutral).

We had to move the inverter to the storage room in the museum because the machine is very noisy mainly because of two large air-movers. Below is a short video showing the machine in action.

We now have the 400Hz Power we need for the project in the sim. This marks the beginning of the instrumentation power-up in the trainer.

L-1011 Trainer: 400Hz Power on GEN1

L-1011 Trainer Installation: AC/DC Power System Complete

L-1011 Trainer - AC/DC Power Control Relays

The AC/DC Power System buildout is finally finished!! A short moment to celebrate :) Getting the power systems right certainly took a lot more than I personally had anticipated. In order to make the power distribution look and feel as close as possible to the real thing we, in essence, built a miniature version of the actual power distribution system with all the AC and DC busses present in the L-1011. This made this a lot more complicated, but also a lot more rewarding. All in all, a good 60 hours went into building the power system.

The two images below show the finished DC and AC systems prior to us dressing up the cables and making it all look a lot cleaner.

L-1011 Trainer - DC System (Pre-Cleanup)

L-1011 Trainer - AC System (Pre-Cleanup)

All this crazy cabling stuff in the two images above is controlled by the neat and easy to read "Electric System" panel on the lower F/E station (image below). However, all the magic behind the panel is implemented with 72 control and sense relays.

L-1011 Finished Electrical System Panel

The image above shows the L-1011 as would be typical at the gate powered by External Power. The three engine generators are off and the FIELD and GENERATOR breakers show "OPEN". The External Power is switched onto the AC Tie Bus and the Tie Bus Breakers (white flow bars) are closed to power the AC Bus 1, 2 and 3. 

L-1011 CPT Installation: External Power and AC Tie Bus

L-1011 CPT - AC Tie Bus Relays

Today we installed the AC Tie Bus relays as well as the EXT PWR relay. The image above shows the AC Tie Bus control relays together with the APU, ENG1-3 and EXT PWR control relays prior to installation into the trainer.

The control relays are all Phoenix Contact 24V DC relays and in turn control the annunciator lights on the Electrical System panel as well as the the power relays in the DC/AC power distribution rack. Below is a short video of the operation of the External Power and the distribution of external power across the AC Tie Bus to the individual AC buses and the flight station power buses.

In case you don't want to watch the video. Here are a few still that first show the AC Tie Bus un-powered with AC External Power "AVAIL" (Available) but not ON.

L-1011 CPT - AC Tie Bus Open

Below the External Power is not switch onto the AC Tie Bus, the three Tie Bus Breakers are closed and AC BUS 1, 2 and 3 are now powered.

L-1011 CPT - Ac Tie Bus Closed and EXT Power ON

The lower FE/SO Station integral instruments light are powered by transformers connected the to AC Flight Station Bus 2. Int he picture below you can see that the instruments illuminate with External Power ON and only the AC BUS 2 tied to the AC Tie Bus.

L-1011 CPT - AC BUS2 Joined To Tie Bus Only

Below is a 2nd short video showing the operation of bringing AC BUS 2 online via the AC Tie bus only.

L-1011 CPT Installation: AC Buildout - Power Buses - AC Tie Bus and Flight Station Buses

L-1011 Trainer - AC Tie Bus and AC Flight Station Buses

Slowly but surely the power distribution for the trainer is taking shape. Today we worked on the AC Tie bus and the AC Flight Station Buses. The image below shows the three AC Flight Station Buses. Each bus has a relay that is controlled from a "R" labeled circuit breaker on the CB3 panel. There is also a 120V relay that is for sensing voltage on the flight station bus to communicate to the computer as well as the annunciator on the Electric System panel.

L-1011 Trainer - Flight Station Buses

Another important AC bus component is the AC Tie bus. The tie bus is used to allow all AC sources to work together or to act as fail over for one another. Below is the AC Tie bus in the current build out phase. The bus has the relays for the three engine generators on the left together with one 120V relay used for sensing power on the bus. Eventually relays for External Power (Ground Power) and the APU simulation will be added.

L-1011 Trainer - AC Tie Bus

In additional to the work on the AC buses we also added a few more instruments to the flight engineer's instrument light bus. Below is how far we have gotten in bringing instruments onto the light bus.

L-1011 Trainer - Integral Instrument Lighting -  Continued

L-1011 Trainer - Integral Instrument Lighting - Continued

L-1011 CPT Installation: AC Buildout - Power Buses

L-1011 Trainer - AC/DC Power System

Started the installation of the AC bus system today. The L-1011 has a number of AC buses and today we started installing the three primary buses: AC Bus 1, AC Bus 2 and AC Bus 3. Each bus has a control relay that turns power to the bus on and off and will be controlled via the Electric System panel on the Second Officer's console. In addition to the control relay each bus also has a relay that turns on when the bus is powered, i use this to "sense" the state of the bus. Below is an image of the 3 primary buses as installed into the simulator power rack.

L-1011 Trainer - AC Bus System

Next will be the installation of the AC Tie bus as well as the DC Power buses. 

Avionics Bending: AC Frequency and Volts Indicators

L-1011 AC Frequency and Volts Meter

The L-1011 Electrical Panel has two instruments that show the AC Frequency and AC Volts measured on a specific subsystem. The image above shows the frequency (left) and AC volts (right) measured directly from the 400Hz Inverter. The instrument on the left indicates 400Hz and the one on the right indicates 115V AC.

Both instruments on the L-1011 had been made by The Lewis Engineering Company which was later acquired by BFGoodrich and closed down in 2000 as a result of the merger. Here is the pinout information for these instruments:

Frequency Meter 152LCF5B

Pin      Function
1        5V AC Lighting (H)
2        5V AC Lighting (L)
3        Chassis Ground
4        115V 400Hz (H)
5        115V 400Hz (L)

AC Volts 152LCV8

Pin      Function
1        5V AC Lighting (H)
2        5V AC Lighting (L)
3        Chassis Ground
4        PMG DC Input
5        115V 400Hz (H)
6        115V 400Hz (L)

L-1011 CPT Installation - AC and DC Power Buildout

AC/DC Power Buildout - L1011 Trainer

The AC and DC Power System buildout is ongoing. Today Jim and I installed a number of components into our Power and Digital I/O system rack. This rack will hold the AC and DC power switching relays as well as the Analog and Digital I/O for the two Simulator Control Computers. All of the power sources used on our L-1011 Trainer are made by German company Phoenix Contact, except for the 120V 60Hz power conditioners and the 115V 400Hz Inverter. In the image below you can see Jim getting busy on preparing the rack for the installation of additional power components.

AC/DC Power Buildout - L1011 Trainer

It's a good size rack that will hold most of the power and the digital I/O as well as the primary control computers. The 24V DC Power supplies (see the following two images) will simulate the actual T/R units on the L-1011. There are 3 engine generator driven T/Rs (we installed them today) as well as an Essential T/R (ESS T/R) and a 24V DC Power Supply that will simulate the aircraft's battery.

AC/DC Power Buildout - L1011 Trainer

Each of the Phoenix Contact Quint Power supplies has an output of 24VDC at 10A. The power supplies have no cooling built into the supply and require external convection cooling. In the image below you can see the fan bank that we installed directly below the power supplies. This fan bank will move air through the supplies and will cool them while they are under load.

AC/DC Power Buildout - L1011 Trainer

L-1011 CPT Installation - AC and DC Power Buildout

115V 400Hz Power Inverter for the L-1011 Simulator

The work on the AC and DC power sources and the distribution systems is ongoing. Today Jim and I worked mostly on placing an 120VAC Power conditioner and a huge 115V 400Hz Inverter into a rack. These two units will become the main power sources for the L-1011 Trainer at the National Museum of Commercial Aviation. The image above shows the 400Hz inverter ... aka. The Beast. Below is an image of the 120VAC power conditioner.

120V AC Power Conditioner for the L-1011 Simulator 

Both power units will be remote controlled via the Electrical System panel in the L-1011 trainer. In order to reduce the amount of thermal output and fan noise in the sim room we are placing the power units outside the sim room in a 19" equipment rack. Here are a few images from the installation work/

120V AC Power Conditioner in Rack

Jim working on the Inverter Base

Jim Working Placing Railes for the 115VAC 400Hz Inverter

120VAC Power Conditioner and 115VAC 400Hz Inverter 

400Hz Inverter Power Feeds

The main power units feed a series of power distribution panels that will simulate the actual power busses found on the L-1011. the units had previously been used on a flight simulator and are currently in bits and pieces. In order to get them ready for installation in the simulator room we are refurbishing the units and testing them prior to reuse.

Power Control Panel Rework for the L-1011 Simulator

One of 3 Power Distribution Panels for the L-1011 Simulator

L-1011 - CPT - AC Power Planning

L-1011 AC Power Distribution Schematic

AC power is used on the L-1011 a lot more abundant than DC power. On the actual aircraft, AC Power is produced by the engine driven generators, the Auxiliary Power Unit (APU) or the on-board battery via an Inverter. AC power on the ground can also be supplied by an external power source. As you can see in the image above, each AC source produces 3 phase output. Therefore, each of the buses, like the AC1, 2 and 3 and the AC Tie Bus are all depicted as 3 phase buses. For the simulator we will not implement a 3 phase system but will use a single (1) phase AC distribution. A single phase will be more than sufficient for the cockpit instruments and the few motor devices that would require 3 phases, such as the standby horizon, we will simply simulate them with DC motors. In the diagram above you can see that there is a AC Flight Station bus that hangs off each of the main AC busses ... the three flight station AC buses are what we are most interested in.

Another key difference between the actual L-1011 AC power system and the one we are using on the simulator is that we will not use 115V 400Hz power for everything. Without motor generators, creating 400Hz power is quite complicated (it requires inverters) and therefore we will only use the 400Hz power for instruments that need them. So here are the AC sources that we will use on the simulator:

• 120V 60Hz Regular AC Single Phase Commercial Power (standard outlet power in the USA) aka. Mains Power
• 115V 400Hz AC Power (Created by an inverter from a 120V 60Hz source)
• 28V 400Hz AC Power (Created with a Transformer from the 115V 400Hz Source)

Below is a diagram outlining how the AC essential bus is controlled.

L-1011 AC Essential Bus

So, for the simulator, all DC Transformer/Rectifiers will be driven from the normal 1 phase commercial power source (120V 60Hz) and the 400Hz instrumentation will be driven by the 400Hz inverter that we have for the simulator. The 400Hz inverter will act as the simulated engine generator power sources and will supply power to the AØ phase.