Review of IMO iSmart

Table of contents

RoadTest: IMO iSmart

Author: cghaba

Creation date:

Evaluation Type: Independent Products

Did you receive all parts the manufacturer stated would be included in the package?: True

What other parts do you consider comparable to this product?: Klockner-Moeller (Eaton) Easy, Mitsubishi Alpha 2

What were the biggest problems encountered?: The absence of the programming cable prevented the evaluation of function block programming of the device. Documentation can be improved.

Detailed Review:

First I must say that this is my first review and I hope will not be the last.

I was very interested in getting my hands on an IMO iSmart as I was working with similar products: the Easy from Klockner Moeller (now Eaton) and the Alpha/Alpha 2 from Mitsubishi.

When roadtest announced I quickly read the specs of the iSmart and I had the impression that it implements the two programming methods Easy and Alpha implements separately: ladder diagram programming for Easy and function block programming for Alpha.

First disappointment was when receiving the package I found out that the smart relay was shipped without the programming cable. Ok, I knew that this smart relay can be programmed using the HMI (the product parts that have such an HMI). The one provided by the roadtest has such an interface.

I must say that lately I worked with Alpha 2 series which comes with a big LCD display making information more visible and programming more easily. I won’t complain too much because the display of iSmart, if back light is turned on, provides good visibility of displayed information.

So now let’s start programming.

Even if programming cable not available, the smart relay can be programmed using its HMI. I don’t advise anybody to start writing the program directly pushing the HMI buttons even if the way how a program can be input using this method is very clear (after reading the programming manual).

Write down the program on paper and after that input it into the relay. The work is considerable facilitated in the case of iSmart as the programming software is freely available and contains also a simulator. The idea is to use the software to develop the application, verify it by simulation and when ok, input it in the relay memory using the HMI.

A good thing is that the iSmart can be programmed using either ladder diagram or function blocks. The problem is that this is possible only using the programming software. Only ladder diagram can be used to program the smart relay using the HMI and even then not all features are available. I hope that a future version of the product will allow programming in both languages using the HMI.

The selected application for testing the smart relay was a galvanizing process where a metallic part is picked from an input store then successively immersed acid pickling, rinse, fluxing and galvanizing bath and finally released in the output store. The picking head moves vertically up and down for immersing into the bath and rising the part from bath, and horizontally from to each bath and store positions.

Two limit switches were used to position picking head up and down and 6 limit switches for sensing the 4 bath positions and the initial and final store position. These consumed 8 of the 10 inputs to the smart relay, the other two being used to start and stop the process.

Two motor are used to implement the vertical and horizontal move, the motors being supplied by an inverter. The two motors are driven alternatively the inverter output being connected to the motors using two relays. These are controlled by two of iSmart outputs, the forward (meaning right move/up move) and backward (meaning left move/down move) being controlled by other two of the outputs. A fifth output is used to control the electromagnet that picks/release the part to be processed.

In order to implement a two mode operation, manual/auto I needed another input. Luckily, the pushbuttons of the HMI can be used as inputs. Unfortunately only 4 of the 8 inputs can be used (compared with Mitsubishi Alpha 2 where all 8 buttons can be used – in case all buttons are used as inputs in the program, a two-button combination is used in run mode to activate the smart relay menu). If you want to use the pushbuttons of HMI don’t forget to activate this option in the Set Menu of the HMI.

I used timers to establish the time the part must stay immersed in every bath and a counter to count the number of processed parts.

I started to write the program using the programming software and I ended with an 83 lines ladder diagram. Writing this program into the smart relay memory using only the HMI can be done but it is not a pleasant task. Next I will give some remarks about using the programming software.

I was amazed of the new (for me) way to write the ladder diagram. When will we have standard way to input ladder diagrams in the programming software? I didn’t work with all PLC or smart relay programming software, though I know a tenth of them, and all have a different way to input the ladder diagram!

          Ok. What I like at the SMT software and always appreciate in this kind of software is the possibility to write the diagram not only using the mouse but also using only the keyboard. This results in an increased productivity of writing the application.

What I don’t like is that in the ladder toolbar, most of the buttons look the same, though they correspond to different programming element types. The types are identified only by the letter inside the button.


Second in dialog boxes it is not implemented an Alt-underligned_letter selection, as for example in Edit Contact/Coil for rapid selection of output types. Third, in Edit Contact dialog box usually the STR contact type is selected by default. Sometimes (possible there is a rule mentioned in the documentation) the STR NOT contact is selected which sometimes may be annoying.

The SMT software includes a simulator that can be used to make an initial verification of the application program. The operation of the program can be visualized on the ladder diagram in the LADDER window or on an animation of the device in the Keypad window. Both windows provide the means to modify inputs either digital or analog and visualize the status of different programming elements (inputs, outputs, M and N coils, analog inputs etc).

In LADDER window, though status of outputs can be visualized in the element list (when the output becomes active, a star appears under the corresponding output number) or in the Element Symbol window (if opened), I would prefer something more visible such in the Input Status Tool.


In the keypad window you can operate the HMI as if working on the hardware HMI. You can enter the HMI menu, make changes, visualizing the operation of ladder diagram (activation of different rungs) as with HMI on the iSmart HMI.

A problem occurred in simulation when using a HMI custom display activated by the Z01 button. The custom display appears for a very short time being quickly replaced by a display listing the AQ values.


The custom display doesn’t shows when repeating the command (push Z01), the AQ display couldn’t been changed anymore but only switching to LADDER window and back.


During this test I could only evaluate only a small number of this product features. In the following days I will continue to discover the capabilities of iSmart but it is really difficult to do it using only the HMI.

I am not used with this kind of behavior of the producers/vendors who provide these devices without the programming cable. In the microcontroller and FPGA world the producers/vendors usually are providing the developing kits with all necessary cables and programming software (though usually with limited functionalities). They have understood that they are microcontrollers or FPGAs vendors and not programming cable vendors and that it is important to provide all necessary tools and accessories for user to have the easiest learning and adoption curve.