In my application there are pulsations. Which pressure switch should I choose?
Is it possible to use Danfoss pressure switches when the medium is sea water?
Answer: Yes, but we recommend using only our diaphragm versions: KPS 43-45-47, CAS 143-145-147, MBC 5000/5100 with diaphragm type of sensor.
What is the maximum/minimum pressure/temperature at which Danfoss switches can be set?
Answer: Danfoss manufactures various pressure switches which can have a setting range of anywhere between -1 to 400 bar and temperature switches from -60 to +300°C.
However, each switch will have its own regulation range as detailed within the product catalogue pages. It is always good practice to avoid choosing a product which will be switching near to the limits of its range.
What is the DIN numbering of terminals?
Answer: Terminal numbers are always ODD for inputs & EVEN for outputs, which explains why the changeover switch in almost all pressure & temperature switches has numbers 1, 2 & 4. The live feed goes in at 1. It comes out at 2 when the pressure or temperature is low (so take this to your pump or heater as a live feed) out of 4 when the temperature or pressure is high. (You can take terminal 4 to a ''satisfied'' tell-tale lamp or to an unloading valve or cooling fan, if you wish).
Is it possible to use Danfoss pressure switches when the medium is oxygen?
Answer: As it is not possible for Danfoss to guarantee a bellow element that is free of oil, we advise customers not to use oxygen together with Danfoss pressure switches.
In principle, our pressure switches will work well with oxygen if the parts in contact with the medium are totally free of oil. If there is oil, there will be an explosion risk.
After installing the switch and making the setting based on scale values, the real system pressure value and scale value seem not to correspond. What is the reason?
Which types of pressure switches have Pressure Equipment Directive (PED) approval?
I am looking for the on/off switch with the highest possible IP protection, what options do I have?
Which on/off pressure switch has the highest vibration resistance?
What is the maximum pressure range for the MBC switches?
How does the manual reset work in relation to on/off switches?
Does Danfoss offer special pressure switches suitable for steam boiler applications?
Does Danfoss offer special pressure switches suitable for sea water as medium?
How can I protect an installed MBC switch against excessive pressure peaks?
What does SPDT stands for?
What is the most common contact system type used in Danfoss switches?
Which is the best choice among pressure switches for marine applications with high pulsating media?
Answer: Pressure switches with a diaphragm type of sensor (types MBC, KPS, CAS) are the most capable for systems where high pulsations occur.
When such pulsations are present, a damping device or pulse snubber should be considered.
What would be the best pressure switch choice for applications requiring high repeatability, accuracy and adjustable differential?
What is the difference between MBC 5000 and MBC 5100 switches?
When is it recommended to use a gold-plated contact system?
Do you have a pressure switch for steam applications, PED approved?
What kind of pressure switch can I choose for a water pump?
Where I can find technical information regarding on/off switches?
Is it possible to order an MBC with short cable and special plug (different then DIN plug)?
Do you offer pressure switches in stainless steel?
What is the procedure for setting an MBC pressure switch?
Answer: 1. Secure regulated pressure source with pressure gauge and state indicator for electric connector of MBC.
2. Connect the unit to pressure source and electrically to indicator.
3. Change pressure slowly and observe indicator.
4. Note down upper and lower snap point pressure.
5. If necessary, turn range screw to change setting and repeat 3. and 4.
6. Mount in the final application.
7. Verify settings with pressure gauge and indicator in the application.
8. If necessary do small adjustments.
9. Good practice - Note settings and date on the small card attached to switch. Inspect setting once in a while. Note inspection results on the same card. Keep track of abnormal events: Other elements breakdowns, servicing etc.
Is a bellows-type pressure switch better than a diaphragm-operated one?
Do we have device for measurement of liquid level of a open tank?
Can I use RT or other pressure switches in steam applications?
I am looking for a simple pressure switch to start up my 3-phase compressor - which one should I take?
Can you confirm that Danfoss does not use "deca-BDE" for pressure switches?
Answer: Our products (including pressure switches) are covered by RoHS Directive and meet its requirements.
This directive bans using some hazardous substances, e.g. PBDE (polybrominated diphenyl ethers) and PBB (polybrominated biphenyls). PBDE and PBB were used as flame retardants in plastic parts. There is no PBDE in our products.
Does Danfoss have a product for controlling the vacuum in a vacuum pump?
Do you have pressure switches with "GOST" approvals for the Russian market?
Do Danfoss pressure switches feature UL, CSA and ETL certificates?
How can I monitor when I have to change the element of my filter?
Which switches should I use for seawater - or other media with particles or depositions?
Answer: In case of seawater you should generally use diaphragm versions of switches:
- KPS 43, 45 & 47
- CAS 143, 145 & 147
- MBC 5100 with diaphragms
Seawater may contain contamination and certainly salt, both of which will likely accumulate inside the application. Not least inside the switch,, because the water inside is almost still (no flow). If salt crystallizes on the bellows surface it can easily affect its proper function.
In case of diaphragms, very smooth and flexible, this problem is less visible. This will cause the depositions to be removed from its surface, and until the whole system is filled and blocked with depositions, it will work.
Depositions are especially dangerous when you have a small bellows - like in MBCs.
If you need to use bellows version of switches then try to choose comparatively big bellows - surfaces on which depositions are stored are comparatively far away and it would take a longer time before they affect bellows function. RT is a switch of this kind.
Where do I find production date on pressure or temperature switches?
For the Pg plugs sold with MBC, which are the recommended cable diameter sizes?