Austin my Father and I, drove up to Nh to fetch one set of parts to assemble a turbine. The goal was to assemble a turbine in Waltham and be able to test everything rather than assembling it in NH. Now that we have been through this process, I understand why its all taken apart. Have you ever put together a Hemnes? or a Stuva or perhaps a Alex from Ikea?
Have you ever found yourself putting together Ikea furniture? At some point you will find yourself in this predicament, you studied the hieroglyphics and it turns out you put something in backwards or incorrectly and you have to dissasemble everything to fix that part. This turbine is like that. In order to say fix the generator which does fail time to time, you have to disassemble the whole thing to get to one part, which is really inconvienient and later you will find out how much of a pain in the ass that really is......
With the turbine housing, generator Bulb and misc bolts and parts in the truck we set out for the dam about fifteen minutes away to get a better understanding of the electrical side of things. The old 1990 F-350 was about at her limits and riding on the rubber helper leaf springs. Its quite nice that this site and all the things on it are at the capacity of the tools and equipment we have.
Here is a picture of happy Austin dragging overgrown vegetation up the hill to our chip pile. One of the things we wanted to do was clear back all the vines and things near the building so we can see whats going on.
In clearing the vegetation we discovered this wall someone at some point wanted to build. The corner of the building is sort of disintegrating, but it doesnt really matter because in this image you can see an Ibeam on the bottom of the building. I Think the way that they rebuilt this generator room back in the 80's was they built a steel skeleton and then put up concrete block walls to keep the wind out. They wanted to pour this new wall to maybe secure the buildings footing?
As it got too dark to work outside we switched to inside work. My dad and Austin were in charge of figuring out what we have, what it does, and if there are any glaring things wrong with anything. As you can see this is the inside of the main cabinet. This cabinet serves the function of connecting the Turbine to the grid, with some interlocks in the middle. There are some current transformers, voltage sensors, phase sensors, and temperature sensors, all of these basically give the green light to allow the turbine to connect to the grid. What this cabinet does is look at all of the conditions and determine whether its safe to connect. If there is a dropped phase, over voltage, under voltage, shorted phase, and many other things it disconnects the turbine. Now, this is all controlled by a PLC and ladder logic. I should tell you again that we have no documentation, no manual, no schematic, just flying blind.
While we were poking around we wanted to see how the 48vdc butterfly worked, and tested to make sure it was happy. You can see from this picture that its a pretty simple device. A DC motor, gearbox and a lead screw, with a nut thats attached to the pivot axel arm. The previous owner told us that the electrical bill goes up in the winter but he wasnt sure why, and we saw on the control panel there was a knob called butterfly heater. Now you would think that this would be some resistors or wire wrapped around the shaft to keep it from freezing, but no..... It was what i suspected which is a 65w tungsten lightbulb with a thermostat. Simple and effective, except that it was burnt out so we replaced it.
We also inspected this gear that moves the spillway gate up and down. At some point in the past this gear was damaged and requires some braising, welding and or replacement. We took some measurements and are waiting from Rob our gear man to tell us how to move forward.
Another fun day at the dam, we are excited to get into the turbine and understand what went wrong and what if anything needs fixing.