Knowing what each slot is used for in our flowmeter modular indicator box with needle indication can help us to avoid errors in reading or operating the instrument.
I bought a flowmeter a few months ago. Now I need to get a continuous signal output to a PLC to know continuously the flow rate (or level) through one of the pipelines of the process. I also need alarm outputs that before, when I bought it, I did not need. The supplier has indicated to me that I can add a transmitter and a limit switch to the instrument I have, so I do not need to buy a new one. They also seem to be easy to install.
I have placed the order, I have already received them and I am ready to install the two elements. I have removed the front cover, removed the graduated scale plate and… now what? Where do I place each device?
Surely this situation is familiar to you. Making it easy does not mean that we know how to do it right away. Here we go, to clarify to you what each slot of our modular housing is useful for.
![SC250-flowmeter-with-complete-modular-housing SC250-flowmeter-with-complete-modular-housing](https://tecfluid.com/wp-content/uploads/2018/04/Caudalimetro_con_caja_modular_completa_SC250-228x300.jpg)
SC250 flowmeter with complete modular housing
Tecfluid have a modular housing that can be used for some of the flowmeters and level meters in our product range.
This housing allows to incorporate switches and transmitters after our purchase, to complete the functionality of the equipment that we bought in the past.
![internal-support-of-modular-housing internal-support-of-modular-housing](https://tecfluid.com/wp-content/uploads/2018/04/Soporte-interior-de-caja-indicadora-300x300.jpg)
Inside of the modular housing
When we remove the front cover and the measuring scale plate, you can see a support with several slots in its lower and upper sides.
What to place in each slot of the modular indicator box
![Ranuras_de_la_caratula_numeros Ranuras_de_la_caratula_numeros](https://tecfluid.com/wp-content/uploads/2018/04/Ranuras_de_la_caratula_numeros.jpg)
Detail of the slots in the modular housing
(lower and upper)
1. From the inside of the modular indicator box towards outside of it, the first internal slot (lower and upper) is suitable for retrofitting the AMD (adjustable NAMUR inductive detector) and AMM (adjustable micro-switch) limit switches.
If you need to know more about limit switches, this article about Limit switches for variable area flowmeters could be of interest for you.
![Adjustable-limit-switch-AMD Adjustable-limit-switch-AMD](https://tecfluid.com/wp-content/uploads/2018/04/Automatismo-regulable-AMD-300x245.jpg)
Installed AMD limit switch
![Adjustable-limit-switch-AMM Adjustable-limit-switch-AMM](https://tecfluid.com/wp-content/uploads/2018/04/Automatismo-regulable-AMM-300x251.jpg)
Installed AMM limit switch
2. The second slot should always be free.
3. The third slot is suitable for inserting the display / totalizer of the TH7 electronic transmitter.
![th7-electronic-transmitter th7-electronic-transmitter](https://tecfluid.com/wp-content/uploads/2018/04/Transmisor-electronico-th7-300x294.jpg)
![Slot-for-totalizer Slot-for-totalizer](https://tecfluid.com/wp-content/uploads/2018/04/Ranura-para-totalizador-300x300.jpg)
4. And in the outer slot we will have to place the graduated scale plate.
![Place-scale-plate-in-modular-box Place-scale-plate-in-modular-box](https://tecfluid.com/wp-content/uploads/2018/04/Colocar-caratula-en-caja-modular-1024x620.jpg)
We must be careful when we put the graduated scale plate. If once placed it seems that the indicator needle is getting stuck or braking, you will surely find the solution in this post about the graduated scale plate and the indicator needle.
“It is very important to place each element in the right slot for the correct operation of the flowmeter or level meter”
Now everything is much clearer, right? Unfortunately, to finish the installation of the new elements and make the necessary electrical connections and other functions, you will have to read the instructions manual that you receive with the switch and / or the transmitter.
However if you do not see it clear or you find yourself with difficulties, do not hesitate to contact the Tecfluid sales engineer who you usually speak to in order to get help.
And above all do not forget that you can send us a message if you would like us to talk about a specific topic in our blog 🙂