Vibration analysis is an established method for fault detection and diagnosis of rolling element bearings. However, it is an expert oriented exercise. To relieve the experts, use of Artificial Intelligence (AI) techniques such as deep neural networks, especially convolutional neural networks (CNN) have gained much attention of the researchers because of their image classification and recognition capability. Most of the researchers convert the vibration signal into representative time frequency vibration images such as spectrogram, and scalogram. These images are used as input to train the CNN model for fault diagnosis. Commonly, fault diagnosis is performed under same operating conditions, where models are trained and deployed for prediction under same operating conditions. However, outside laboratory environment, in real world applications, different operating conditions, such as variable speed, may be encountered. With the change in speed, characteristic frequencies of vibration signal will also change, which will result in changing the vibration image. Consequently, performance of CNN model may drop significantly for prediction under different operating conditions. To get the training data from all potential operating conditions may not be feasible for most of the real-world applications. Therefore, there is need to find some signal properties which are invariant to change in operating conditions and only change due to change in health state. So that models trained under one set of operating conditions may predict correctly under different operating conditions. This paper proposes a defect diagnosis method for rolling element bearings, under variable operating conditions (speed and load) based on CNN and order maps. These maps exhibit consistent properties under varying speed; therefore, they can be used to train the CNN model for fault diagnosis under variable speed. Effect of load change on these order maps is experimentally studied and it is found that proposed method can do fault diagnosis of rolling element bearings under variable speed and load with high accuracy.