Last week was a quiet week.
There was no training on Thursday and Friday. At the moment there are so many broken machines that need to be repaired urgently. All available staff are busy with repairs, there is no time for training.
I sat alone in the room, obviously the only one who didn’t notice. After almost an hour, Benjamin came by and let me know.
Since I was already there, the boss of the electricians approached me. A colleague from the Philippines. He asked me if I knew anything about inverters. They have a soft starter that is currently causing problems. I wouldn’t say I know about it, even if I can roughly figure out why it’s needed.
It made me think of my dad.
When I was little and I was interested in training as an electrician, he explained his circular saw to me. And what I remember well is that when you switch on the circular saw, you first switch on the three-phase motor (380 V) in “star connection” and let it run up without load. Only when the speed of the motor has reached the nominal speed do you switch from star connection to delta connection.
This is done to reduce the starting current when switching on. When the motor is running, it is then switched over and the current has no starting peak.
A saw is a saw, I thought 🙂
Even though the saws here are larger. Approx. 120 kW. At idle the current is about 100A at start-up it would be more than 400A. This peak would overload the generators of the own power plant, so they can’t increase the power that fast. And that’s exactly why they have a soft starter, to limit the starting current.
Honestly, I have no idea what the problem is with the soft starter. He handed me the manual. So now I have something to read over the weekend. By the way, it’s a German manufacturer, Schneider Electric.
At the same time I got a little guided tour.
First the sawmill, where the tree trunks are cut. This is the first time I’ve ever seen the inside of a sawmill.
Then we went on to the next hall, where veneer is produced.
The individual veneer layers or sheets are about 1 mm-8 mm thick and are planed off the tree trunk. These are also huge machines. Either the planer moves and the wood is fixed, or with the newer machine, the wood moves. It can do up to 80 strokes per minute and thus 80 sheets per minute. This moves a log of about 6 m length and 80 cm thickness.
Afterwards, the veneers have to be dried so that the residual moisture content is below 5%. After drying and packing, the veneers are ready for shipment.
Only processed timber may be exported from Ghana.
Logs that have not been processed – whereby cutting to length is already processing – may not be exported. This is a sensible law and ensures that this part of the value added stays in the country. The machines and technology for processing are very simple and can be operated and maintained here without any problems.
Leave a Reply