Upgrading your old dyno to PEREK dynamometer system

PEREK dynamometer controller is designed to be easily adapted to any dyno hardware. Along the way, there are some points to check to get your dyno up and running quickly.

Dyno rotational inertia

Before you throw out your old controller, you may check if you can access some information that may shorten setup of the new system. One thing you need to look for is your dyno rotational inertia. It is a value somewhere in range 3kgm² – 60kgm². Getting this value from old software will eliminate the need to calibrate it yourself.
If you can’t get this information, don’t worry, the dyno software have some tools that will help you to get this value right. Dyno inertia help article.

Rotational speed signal

To get your dyno running, you need the rotational speed signal. It can be generated with few types of sensors. These are the options you can have in your hardware:

  1. Encoder – Supported by DC1L, DC1E4 and DC2 series controllers.
  2. Hall sensor with toothed wheel – Supported by all DC1 and DC2 series controllers
  3. Variable Reluctance (VR) sensor – Not directly supported by DC1 or DC2 frequency inputs. Can be used with VRI1 adapter or be connected directly to Engine Speed input.
  4. Damaged or missing sensor (toothed wheel is present) – You can buy HS3 hall sensor, but compare your toothed wheel geometry with “suggested toothed wheel dimensions”. The sensor may not work with much smaller tooth geometry.
  5. Damaged or missing sensor and wheel – You can equip your dyno with encoder or toothed wheel with HS3 hall sensor. Encoder ease of installation and sometimes a bit lower cost may be tempting, however encoders are delicate and fragile devices. Toothed wheel with hall sensor is robust, have no wearing parts and will last for years. In terms of accuracy, both solutions are excellent.

Encoder or hall sensor voltage
You need to check supply voltage for your sensors in spec sheet. Voltage available at frequency input connector in DC1L, DC1E4 and DC2 series is 12V. If you need to, you can get 5V or 24V (24V only in DC1E4 or DC2) from other connectors.

Eddy current absorber control

An eddy current brake is a device that needs some significant power to generate the torque that you need. For supplying this power, you need eddy current brake “interface” / “power stage” / “power supply”.
The dyno controller can send signal to brake power supply in form of digital PWM signal or analog signal. PWM signal is from open collector output with pull-up resistor. Analog signal is in range 0-10V, and it can be configured to lower range (i.e. 2-5V). If your old controller has a power stage that can accept any of these signals, you don’t need to change it.
If your power stage is missing or broken, you need to buy one. You can get affordable, but slower BD2 interface or faster BD3 interface.

Brake torque measurement / load cell

To measure torque generated with your eddy current brake, you need a load cell. If your dyno already has one, you don’t need to change it. The software allows calibrating the load cell that you have. If your load cell is broken or missing, you can get one here. To choose suitable load cell size, you need to know your eddy current brake torque and load cell torque arm.
Minimum load cell size = brake torque / arm length / g * safety factor
Example: Eddy current brake torque = 1500Nm, arm length = 0.5m, g = 9.8m/s², safety factor = 1.2
Minimum load cell size = 1500Nm / 0.5m / 9.8m/s² * 1.2 = 367kg
We take 500kg load cell.
Safety factor is required because of the vibrations that the dyno generates. If you omit it, you may get a clipped, distorted signal near the end of load cell range.

Load cell signal amplification for DC1 series controllers.
Load cell signal is needs to be amplified before it is fed into DC1 controller input. It can be done with amplifier from your old controller of amplifier built in BD1 brake interface. If you don’t have any of these, you need to get the LCA1 load cell amplifier.

DC2 series controllers have a built-in load cell amplifier and don’t need an external amplifier.

Other additional sensors

All other sensors that you need to use such as boost pressure, NTC temperature sensor, EGT thermocouples etc. can be connected to free controller inputs. Sensor characteristic can be freely calibrated with multiple point calibration.
AFR/Lambda sensor can be also connected to the dyno controller, however it requires separate lambda sensor controller. Any controller that has analog output can be used. If you don’t have any, you can use Ecumaster Lambda to CAN.

Dynamometer actuators and accessories

If you need to control some additional devices of your dyno, like roller locking brake, lift, fan or wheelbase adjustment, DC1/DC2 controller has a lot of additional outputs that can be used for that purpose. These are 230V relay outputs and low side transistor outputs. All these outputs can be controlled directly with keyboard keys. If you need, outputs control can be automated with programmable logic functions available in dynamometer software.