Author: Ronald Perek

This time the upgrade target was a German classic: Bosch FLA206. It’s a very popular 4×4 braked dyno from Bosch. Some of you may also know the Bosch FLA203 which is the 2WD version of the dyno.

The stock control system has some time on its clock. It runs from a 3½-inch floppy disk.

In the bottom part of the cabinet you can find bulky power modules, contactor for fume exhaust and relays for wheelbase and lifts. All this is separated from the mains power supply with a with three-phase AC filter.
Despite 3 phase power routed to the cabinet, each power module is supplied with single 230VAC phase voltage. We decided to replace them with three-phase supplied PEREK BD3 modules with fast demagnetization to achieve faster eddy brake response.

Thankfully, the electrical schematic was available at hand. Everything perfectly described and labeled as you can expect from Bosch.

With help of customary German drink, I worked on replacing power modules with modern PEREK BD3 eddy brake power supplies and the main computer with DC1E4 dyno controller.

Precise power measurement requires load cell calibration. My faithful calibration arm and precisely weighted calibration mass helped me with that.

We set up the dyno to display its modern interface on a big TV screen to be visible to the operator in the car and to customers in the waiting room. The dyno can be easily operated this way with use of a wireless keyboard and mouse.

All the dyno functions can also be controlled conveniently from inside a vehicle with a wireless industrial tablet. This includes measurement, analysis and reports, as well as the control of fume exhaust, cooling fans, wheelbase and lifts.

The PEREK system parts used for this conversion were:

• DC1E4 dyno controller
• 2x BD3-22.5A-600uF eddy brake power supplies with fast demagnetization
• 2x LCA1 load cell amplifier (gain 74)
• 4x VRI2 variable reluctance sensor adapter

Stock speed signal sensors and wheels, as well as the load cells, were reused.

Additionally, I installed two VFDs for variable fan speed control and some extra dyno sensors for lambda, temperatures and knock measurement.

This November, I visited Freaks Motorsport tuning company in Belgrade, Serbia. The task was to make wiring, setup and calibration to run AWD Dynocom DYNO X dyno on PEREK controller.

We decided to replace the speed sensors and load cells. The owner received the package from me, so he could manufacture all required mechanical adaptations before I arrive.

The parts required for this conversion were:

• DC1E4 dyno controller
• 2x BD3-22.5A-600uF eddy brake power supplies with fast demagnetization
• 2x S-type 500kg load cells with LCA1 amplifiers and rod ends
• 2x signal wheels and speed sensors

When I arrived, the speed sensor and signal wheel were already in place and ready for wiring.

On the first day, I made wiring for the dyno, and we calibrated the load cells.

Dynocom had a nice eddy brake connector, which we reused for new wiring.

The dyno is equipped with two Frenelsa F16-125 eddy current brakes. We calibrated the load cell for it with 59kg on 2.75m long arm which gives 1600Nm calibration torque.

The next day, we tested automatic dyno fan control and wheelbase regulation to the dyno. Dynocom wheelbase is regulated with a pneumatic actuator that is controlled with three small valves. The valves use so little current that these can be powered and controlled directly from DC1 dyno controller without an external power supply.

After we had the wheelbase and fan under our control, I started tuning eddy brake PID controllers with my Toyota tuning tool 😉

After PID tuning, I measured the dyno moment of inertia to be sure that the software compensates for it correctly. Double ramp calibration method pointed to the value of 2.6kgm².

At this moment, the dyno was fully tuned and calibrated, and the time came to instruct the owner how to use it and to test how well the Dynocom hardware can cope with a more powerful car.

Using OBD feedback in steady state mode allows compensating for engine-roller speed ratio change due to changing tire load and vehicle position on the roller. This mode will keep your engine speed at a precisely set value, even on chassis dyno.

After all final checks and tests were done. What I left in Belgrade was a well functioning dyno and a happy customer!

Polish entrepreneur and winner of the Dakar Rally

Rafał Sonik is a Polish entrepreneur who has been winning in quad rallies since 2001, including the famous Dakar Rally.

Task:

Rafał’s team independently built an inertial dynamometer dedicated to work on ATVs. The dyno is compact and convenient to carry when it is not needed. It is equipped with special ramps and mounting points designed for work with ATVs. The only thing missing was a measuring system. The inertia of the dynamometer rollers was known from the CAD program, but the inertia of additional elements rotating with the rollers was unknown.

Solution:

The dyno was brought to life by a universal PEREK dyno controller. The inertia of a set of rollers and wheels of the quad was measured by accelerating the entire set with a falling weight on a line pulled through the pulley. The dynamometer is now ready to contribute to Rafał’s next successes.

Automotive electronics manufacturer

Ecumaster is one of the fastest growing companies in the motorsport and tuning electronics industry. PEREK works closely with Ecumaster, developing intelligent electronic solutions for the automotive industry.

Task:

The dyno was controlled by software running on an outdated computer. Upgrading the computer was impossible due to the software’s compatibility only with specific computer components – motherboard and sound card. A failure of the dynamometer computer would result in the need to look for specific old components on the used parts market.

Solution:

A PEREK dynamometer controller was used to control the dyno. The controller works with the already installed rotation sensor and toothed wheel. The dynamometer has been calibrated to the inertia of the rollers based on the settings from the old software. The controller is mounted on the back of the dyno TV and is equipped with a wireless keyboard and mouse. The cabinet containing the previous desktop computer has become redundant.