Things are working great. Then suddenly your cement will not weigh up. If you are like most people, you’ve become so accustomed to the concrete batching system running the plant you immediately assume something has gone wrong with the batch system. Not so fast though, there are a ton of variables involved.

The above example, not able to weigh up cement, is actually an easy problem to solve compared to some others you will encounter. So how do you figure out if it’s the plant or the batching system? Actually, there is a rule of thumb we’ll cover but first look at all the possible variables found in most modern concrete batching systems:

1. Electronic output device. This is enabled from the concrete batching system and enables voltage to be sent to a specific plant component like a butterfly valve solenoid or motor starter. This device could have failed.
2. There are generally multiple fuses or breakers in line between the computer and the device being controlled that could be out.
3. Air pressure. Most devices on a concrete plant require air pressure to operate. While obviously there are exceptions, this is another potential source of failure if you have even low air pressure because many solenoid valves will not operate under a certain pressure.
4. Mechanical binds. While not common on a well-maintained plant, mechanical binds can still occur and are absolutely a common source of problem on plants maintained much less frequently.
5. Solenoid valve. If the item failing is controlled by a solenoid valve, the valve could be plugged up, especially in the area of the exhaust port.
6. Got oil? Yep, oil is required in most air lines. There are some systems that claim to never need oil and that may be true for a time. Our experience, however, has been that sooner or later even they tend to need oil like the traditional devices. Lack of oil in most systems will absolutely cause problems.
7. Motor starter. If the item failing is controlled by a motor starter, the high voltage that the motor starter switches out to the motor could be out. This might be because of blown fuses or a transformer that would still allow your low voltage power (room lights) to be on keeping you unaware of this situation. It could also be the heaters on the motor starter have tripped or even the coil of the motor starter itself.

Is this an exhaustive list of every possible thing that could be wrong? Absolutely not. The variables and possible combinations make that almost impossible. Still, it’s a good place to start to check these items because normally you’ll find it is one of these in the list 9 out of 10 times or more.

But what about that rule of thumb? If you have a high voltage manual panel, the rule of thumb is that if you cannot do it manually, neither can the concrete batching system.

What if you have a touch screen or low voltage manual panel? In this case, you would need to rely more on the list above to move through the steps of troubleshooting.

Of course, feel free to contact us with questions. Decades of experience on different plants all of the world has given us the experience to help.