SCRLogic is a software simulation package for training rig electricians to troubleshoot SCR systems.

SCRLogic - The SCR Logic Training Simulator Software for Rig Electricians

Although it is based on a Hill Graham Controls Land Rig, the control philosophy is almost identical to Ross Hill and similar systems, and the fault-finding techniques learned by using the software can be applied to a whole range of equipment.

The software is built of two parts: the graphic representation of the system equipment, and a mathematical simulation of the analogue circuits. The student can probe terminals on the simulation screens and measure the voltage at each point. Faults can be applied to the circuit, which then allows the student to practice identification of faults by understanding the schematics and the observed measurements.

Faults can be introduced manually or from a pre-defined timed sequence of events controlled by a script running in the background. Scripts can be customised and saved and can create complex scenarios which will test the abilities of the most experienced technician.

The simulated system contains four SCRs, dual motor Drawworks, a Rotary Table and two parallel-motor Mud Pumps. Access is available to all four SCRs, the Drillers Console and Foot Throttle, blower MCC starters and the motor terminal boxes.

Note that SCRLogic incorporates no generator control logic because the system complexity lies with the DC Motor and Auxiliary control circuits.

This program assumes that the user understands what an SCR system is, what it is used for and how it works, and is familiar with the terminology associated with a drilling rig. However it could be used as a training aid to introduce SCR systems to electricians from an industrial or domestic background.

To understand the full capabilities of SCRLogic CLICK HERE to download a copy of the User Manual.


The software has complex calculations to perform to simulate the analogue circuitry, so a Windows (version 7 or later) PC with plenty of memory (at least 4GB) and a powerful CPU will improve the user experience. The software will run on 32-bit machines, but these may experience memory problems due to memory fragmentation, so 64-bit is recommended. A mouse with a scroll wheel is required.

A demo version of the program is available as a free download which can be upgraded to a fully licensed version later. The demo version has some limitations on usage (most notably scripting and a limited number of faults) and will time out after 20 minutes of use. To unlock all the features a full license is required.

Click on the link below to download the setup files. Open the the downloaded ZIP file and extract the files to a temporary folder on your computer, then run setup.exe. Follow the prompts to complete the installation.

Name: SCRLogic
Published: 29th September, 2017
Publisher: Contrelec Limited
Downloads: 87
The following prerequisites are required:
  • Microsoft .NET Framework 4.7 (x86 and x64)
If these components are already installed, you can launch the application now. Otherwise, click the button below to install the prerequisites and run the application.


To unlock all the features of SCRLogic please purchase a license by CLICKING HERE and completeing the on-screen instructions. Alternatively you can license your copy of the software from within the program by clicking BUY LICENCE under Help->About SCRLogic.


MCCLogic is the little brother of SCRLogic – a simulation of a motor starter as commonly found in Motor Control Centres (MCCs). It is free and completely unrestricted and includes the scripting capabilities which are restricted in the SCRLogic demo.

To experience the full capabilities of the scripting features try MCCLogic.

Important Notice

As of June 17th 2021 Contrelec Limited shall not be accepting new business

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