Connecting to the grid - May 2013

Here’s a quick summary of what I had to refresh myself on about electricity while we installed our system. Alternating Current, or AC, is a current which periodically reverses direction, expressing itself as a sine wave, meaning that there is a period during every pulse of electricity when no power being delivered to the system. This period is extremely brief, however it is noticeable with adequately fast recording devices; electronic engines built for AC have compensatory mechanisms to provide for their smooth running. Direct Current, or DC, is a steady, direct line of power.

In addition to current type, there are two basic modes of delivery: mono-phasic and bi-phasic. Mono-phasic, as we have in Ecuador, carries the AC current over a single cable, biphasic carries two staggered AC currents over two different cables, and both have an additional grounding cable. Whereas mono-phasic systems are in a powerless period of flux for the entire “negative” or “reverse” of their sinusoidal pulse, biphasic systems combine the staggered currents, resulting in a shorter “reverse” flow period and a more efficient system. For our installation the significance of this is that electric connections in Ecuador have only a positive and a ground, as opposed to a positive, a negative and a ground.

We began the electrical installation with a single wooden poll we placed at the front right side of the house. We strung a thin metal wire from the utility poll at the properties edge to our installed poll by the house and then from that poll to the brick and concrete column supporting the roof atone corner of the small ground-level porch abutting the front entrance. To this wire we attached a super-flex cable: three smaller cables fit into a large rubber tube. When we bought the main cable to carry the current from the utility poll to the house we didn’t yet know that Ecuador uses a mono-phasic system and therefore only needs two cables, the positive and the ground. The price difference is about ¢0.70 per meter, and at over 50 meters of cabling we lost $35 through our ignorance; the next day we bought proper mono-phasic cabling for the lights and electric outlets. Next, we put a hole into the brick wall just below the ceiling at the convergence of the front porch walls, and we fit the super-flex cable through the PVC

tubing we are using as cable housing. On the other side of the wall the super-flex cable passes into a side-hole in a plastic housing box attached to the wall and passes out of a bottom-hole to continue into the fuse box. From there we have the cables for the lights and outlets (much smaller in diameter than the super-flex cables) leave in tubing and run their current to two outlets and a light in our room, one outlet (connected to the super-flex because we needed more volts for the washing machine) and a light in the larder, and an outlet and light in the guest bedroom. We’re waiting until we progress more on the house to buy more materials for connecting the two lights and kitchen outlet outside on the rear veranda. Wire, cabling, PVC tubing and wall mounts, screws, outlets, light switches, lights, fuses and fuse box all included we paid about $400 for the electric system.