Official SF800 FAQ

[Xilikon]

Since I will be getting mine very soon, ladderman is toying with one currently and few others already own one (either from a former group buy or ordered directly from Swissflow), I think it's time for us to have a official thread about the SF800 flowmeter, especially when I will send mine to Martinm210 for some pressure drop testing and possible review. I already feel that this will bring more interest on the SF800

First of all, here is the specifications of the SF800 as taken from Swissflow :

Technical Specifications
Data based on water at 20°C (68°F)

Range
Flow velocity*: 0.5 – 20 litre per minute
Temperature: -20 – +90 °C
Operating pressure: 16 bar
Max. pressure: 40 bar

Technical information SF-800
Process connections: 3/8” hose barb; 3/8”BSP Male
Exitation: 5 to 24 VDC, 12 to 24 mA
Power consumption: 12 – 36 mA/s
Material: PVDF, Vectra (rotor), Viton or EPDM
Output frequency: 100 to 2000 Hz (depending on the flow velocity)
K-factor: +/- 6100 pulse/litre
Length cable: 15 cm standard (different length on request - Dirk confirmed that you can order with the needed wire length, just put a note)
Connector electronics: 3-wire flat cable sealed in housing (jack-plug or molex connector on request)

Reliability
Interchangeability**: +/- 2.25 %
Accuracy: +/- 1.00 %
Reproducibility: +/- 0.30 %

Medium
Medium type: clear or translucent liquids capable of transmitting infrared light
Viscosity: 1-1000 Cst
Examples: water, chemicals, oil, beer, syrup

How the SF800 work (Working Principle) ?

The geometry of the rotorhousing (causing a radial flow in) in combination with the light-weight Vectra rotor (0,04 grams) makes the rotor float in the medium. Because the rotor floats, the measurement process is nearly resistance-free, guaranteeing high accuracy, durability and linearity .

An integrated PCB emits an infrared signal, which is interrupted by the three blades of the rotor. SMD components interrupted transform the signal into a pulse. Because of the construction of the rotorhousing, the Swissflow flow sensors are practically insensible to high pressure.

The materials used (PVDF and Vectra) are to a great extent chemical-resistant and temperature-durable . Contrary to many other fluid flow measurement systems, the Swissflow sensors do not have to be calibrated .

There is also a pps presentation made by Swissflow to introduce the SF800 available here.

Here is the internal assembly diagrams :



Why it's a great flowmeter ?

So far, it looks like it's one of the least restrictive flowmeter in the market, which is perfect for the current watercooling loops. ladderman did some rough testing and it looks like the same restriction as a EK FC8800 block (with 1/2" tubing, possibly almost nil with 3/8" tubing if further testing confirm this).

Is there any reviews about the SF800 ?

Here is a few we found so far :

effizienzgurus.de article on flowmeters (translated)
ladderman's crude review

How to connect the SF800 to the current loop tubing ?

First of all, you need to read the guidelines in the leaflet back for some precautions (it come with a 10 year warranty so it's wise to follow them) :


The SF800 come with a male 3/8" BSPP on both ends so we need a coupler to be able to use with a G1/4" set of barbs. Here is some possible sources for those couplers :

UK : http://www.airlines-pneumatics.com/w...ctCode=s010104 (order code 103031)

US : http://www.mcmaster.com/ (item code 4860K675, not to be confused with 4860K657 which is a G3/8" to G1/4" adapter for Thermochill radiators)

Canada : <Currently attempting to source a online store, possibly http://www.adaptall.com/ to be confirmed by a phone call>

Alternatively, we can also order a 3/8" to 3/8" coupler and use a pair of Thermochill barbs sold by NCIX.

How can I monitor the SF800 signal ?

Currently, there is 3 possible ways to obtain the signal feed from the SF800 :

-Plugged on the motherboard fan header.
-Plugged on the T-Balancer Sensorhub.
-Plugged on the Aqua Computer PowerAdjust (radiical_53 commented about this possibility, to be confirmed).

When do I use the resistors as asked in the schematics sheet included with the SF800 ?

If we want to connect the SF800 on the motherboard fan header, you need to solder 2 resistors to make it work and the diagram is found on the SF800 installation guide included with each bag. The 50ohms/V mean you need to calculate 50 ohms for each volt you want to drop and the difference between the fan header and the 5V feed of the SF800 is 7 volts so you need a 350 ohms resistor.

Here's the picture of the schematics included in the package :


With a M-Cubed Sensorhub, the resistors is not needed but you need to make sure the sensor plug wires is ordered like that : GND - 5V - SENSOR when viewed from above (In other words, the ground wire should be on your left and the sensor on your right). If you are unsure, just look at a fan lead and you will notice the black (GND) is on the left, red (power) on the middle and yellow (RPM) on the right.

For others, I'll add more informations as more people confirm the workings.

How can I get the proper LPM/GPM reading ?

<To be filled>

Is there any worklogs of users with a SF800 in use ?

Yes, there is at least one with a CryztalFontz LCD : http://www.crystalfontz.com/forum/sh...&threadid=4452
Custom mod for readingthe flowrate on a custom monitor (electronic soldering skills required) : http://www.turbokeu.com/myprojects/flowmeter.htm
<more to be added - post or PM me if you want to add yours>

Be noted this FAQ is a work in progress and will be expanded with more informations coming from me and other SF800 users. If you have extra informations, comments or useful links about the SF800, please post and I'll add in the thread

[Jedda]

Here is a translation of the german efficiencyguru's article on flowmeters, including the SF800.


Working Principle

The geometry of the rotorhousing (causing a radial flow in) in combination with the light-weight Vectra rotor (0,04 grams) makes the rotor float in the medium. Because the rotor floats, the measurement process is nearly resistance-free, guaranteeing high accuracy, durability and linearity .

An integrated PCB emits an infrared signal, which is interrupted by the three blades of the rotor. SMD components interrupted transform the signal into a pulse. Because of the construction of the rotorhousing, the Swissflow flow sensors are practically insensible to high pressure.

The materials used (PVDF and Vectra) are to a great extent chemical-resistant and temperature-durable . Contrary to many other fluid flow measurement systems, the Swissflow sensors do not have to be calibrated .

[Jedda]

A bit of impulse info translated from german in the M-cube SDK -

How can I interprete the values from the T-Balancer?

- FanMaxSpeed: add the low- and high byte to a 16bit value (256*HB+LB), multiply it with 10.5 to receive the value for turns per minute.

- Fan RPM and Volt are only interpolated values. RPM is linear interpolated from maximum, and voltage is quadratic interpolated (results from root mean square from ideal rectangular signals)

- The flowmeters are a little more complicated. You receive a simple impulse count value. But this value is dependent from the measuring windows (1 to 4 seconds) – 235 TWI_SHWerte[10]. The 232 and 233 then means the measured pulses per second, 2 seconds, 3 seconds or 4 seconds. Divided through the window width you get the pulses per second, multiplied to 60 seconds you get the pulses per minute. To get the liter per minute or hour you have to respect the adjusted flowmeter dependent pulses/liter value. Our standard flowmeter have 509pulses/liter. This value can be found in the TBAN database on the table “Einstellungen” with the keys “Durchfluss1” and “Durchfluss2”.

-Getting the pulses is similar to pumps and fans, but not exactly. It is only usable without damaging something, if the impulse function works with an open drain circuit. Standard fans uses the 12V for reference, the flowmeters are not powered their self and receive only 5V from the sensor hub. The signal input on the sensor hub is only build for 5V input. You only have to connect ground and pulse with a pushbutton to get an impulse.

[Xilikon]

Great notes, I've added a part in the FAQ and I'm trying to decipher your last post about M-cube in layman's terms

[Xilikon]

I just sent a email to Dirk with a few questions which needed to be clarified like the need to use resistors if plugged to a Sensorhub or any other plug which feed 5v. With the answers, I'll add in the FAQ.

[Xilikon]

Got a reply so I updated the FAQ with the answers. He also confirmed that the resistors is only needed if it is connected to anything which feed more than 5V.

[Jedda]

Thought that was the case but its good to know for sure.
Have asked Urlo about the impulse rate versus the 509/liter normal rate. We'll see what he replies.

[Xilikon]

IMHO, I think you need to edit the impulse rate field so it use 6000 instead of 509. i did some math on ladderman's case and i think this value is accurate.

[Jedda]

It'd be good if it is that simple. Not sure about Jim's weird lowest figure and Ladderman's reversed readings though.
Possibly the sampling interval (1 sec, 2 sec, 4 sec) might be a factor.

[Xilikon]

Yeah, I guess... I will try myself with the resistors and direct plug to the motherboard then use Samurize to get the reading to experiment if there is issues.

[Jedda]

Heres an idea. I may see if I can split the signal to a mobo fan sensor connection and get MBM or Everest to report ltr./m flow. This is easy, as the sensor produces exactly 100Hz per litre per minute pulses (e.g. 5 ltr./m comes out as 500Hz).

[Xilikon]

No, it's 100 Hz per liter PER SECOND, 6000Hz per liter per minute. However, with the fan header, it should be very easy but don't forget to add the resistors as instructed to make it work.

[Jedda]

Yes, of course.
That's what happens when I post at 4 AM.

[Xilikon]

I got the SF800 package from Dirk last friday so here's the goodies while waiting for some tests :

Whole package contents (notice 2 SF800 given as samples ) :


Package leaflet with the schematics and the resistors to add if you are plugging in a header feeding more than 5V :


Back of the same leaflet :


A shot thru the hole to see how big :


Here's mine with the adapters fully assembled using 1/2" fittings (in reality, it looks more like 3/8", which is a bit restrictive) :


A pic of the flowmeter header (the wires order is not correct and should be GND - 5V - Sensor and not 5V - Sensor - GND, to be fixed later) :


Shots of the internals drawings in the included booklet :



I have packaged the 2nd one to be sent to Martinm210 for pressure drop and flowmeter accuracy testing so expect the results in a few weeks (he has all the time since I have my own SF800 so no hurry).

Look also in the first post with the same pics to be used as reference.

[joecop120]

Where can you buy one in the US?

[ladderman]

Originally Posted by joecop120

Where can you buy one in the US?

At the moment you need to buy them direct from SwissFlow. They retail for 25 Euros plus shipping I’m unsure what the cost is to the US, but its 7 Euros to the UK.

[Xilikon]

Yes, just send a email to info@Swissflow.com and they will try to accomodate you. They will sell for 25 euros as ladderman said + shipping costs to your own place.

Also, if you can wait a bit, I might be able to organize a group buy to cut the shipping costs a bit and to get a custom fan header extension with the resistors already soldered.

[Xilikon]

I added the pps presentation of the SF800 that I received from Dirk with my first inquiry email : http://pages.videotron.com/xilikon/SF800.pps

I added that link on the first post too.

[85turbo]

Xilikon.

i would be very interested in one of these with the resistors and a mobo fan header attached.

please pm me if you manage to put a group buy together.

jason.

[Xilikon]

Sure

At first, I will review it and Martinm210 will do it as well. When it's done and published, if the data is promising and it's very easy to use with the adapter, I'll setup a group buy for sure.

[Talonman]

I would want in on that. Might go nice between the PC and the Keg?

[Xilikon]

Sure, I think hopefully you will just need a fan header on the motherboard and a software to read the flow. My own testing will uncover those requirements but it should be pretty easy with a good guide in the end.

[headala]

Any updates?

[Xilikon]

Right now, Martinm210 got my 2nd SF800 and just received a new BSPP 3/8" tap. He will be making a pair of brass fittings for the SF800 and I expect him to start testing shortly.

As for mine, I'm waiting for the resistors to get delivered to my home then I'll start my own testing as well.

[Xilikon]

I finally got around to buy the needed resistors so here's my small HowTo with pics on building a adapter :

Here's what you need :

-2200 ohms resistor (the one with 3 red lines)
-350 ohms resistor (if the store doesn't carry them since it seems to be non-standard, get a 360 ohms since it's only a few millivolts difference)
-A fan extender wire that you can buy at any store. Mine is coming from my now defunct VLSys L.I.S.2 LCD display and it's very long.


First of all, since the 2 resistors will meet at one end, just twist them together :


After this, splice both red and yellow wires (red is +5V and yellow is sensor) then connect one end of the 2200 ohms resistor to the yellow wire. Connect one end of the 350 ohms resistor to the red wire and connect the twisted end to the other end of the red wire. Make sure the yellow wire is continous. Here is a picture about how it all come together :


Since this will be part of my own project, I also sleeved them for a neat look :


That's all. I did a preliminary by connecting the SF800 to 2 bits of tubing, put a funnel at one end. I connected the SF800 on a fan header and opened SpeedFan. Then I poured water thru the sensor and in the bucket while looking at the fan sensor. Depending on the flow, the speed is fluctuating meaning it works. Remain to put it in a closed loop for a real-life testing and that's what Martinm210 will do as I won't disassemble my loop before receiving 10 feets of R-3400 tubing.

Martinm210 is currently preparing the 2nd one with very nice adapters in delrin (a real gem IMHO) and we are talking about the resistors. The HowTo I posted will also help him setup the same thing.