this kind of optic fiber is probably only plastic so for a full DIY , you can use also fishing wire with a big power led or an old chistmass tree optic fiber lighted.....
@kimot in theory you might be right, but in practice... it just works. The propability of collisions is extremely low and this is, as far as I know, the only problem you can worry about. After all, it was not my idea to use MySensors with RS485:
https://www.mysensors.org/build/rs485
@NeverDie Thx for appreciating the work done. There will also be an open source part in the future. When and how extensive the open source part will be, remains to be seen. The release of certain information (block diagram, ..., in this post) is related to those open source parts.
There are some OBD solutions, however most of them (in my experience) give back low frequency data put by the car manufacturer on the OBD-bus (CAN, ...). Therefore transients evolving directly from the battery could only be recorded if the manufacturer sends those data accordingly on the bus. Due to the small bandwidth(also because of other car data that have to be sent, ...), such battery data are sent more often once per second or less. Fast battery events (i.e. cranking events, ...) are therefore imperceptible. Unless the manufacturer processes the fast events and then sends them (once per second or less), which is very unlikely if the manufacturer does not market this feature itself. Third parties devices for high frequency sensing costs several hundreds dollars.
In my experience, important battery states (especially the fast ones) are recorded by measuring and processing corresponding data directly on the battery.
I agree with you about the limits related to the communication over Bluetooth. But i think Bluetooth 5.0 will improve a lot. However, WiFi will always remain an important option due to the high data throughput. The combination of both (BLE & WiFi), especially with regard to energy consumption, will gain in importance.
@bisschopsr said in BlackCircle Sensor - High "WAF" Temp/Hum. sensor:
Hi All,
Like the design thinking of this, although an older topic I did manage to get me one of these dishes. After taking it apart, I have one question that came to mind. Is the ventilation in the dish enough for the humity sensor? Is there any experience with that after running this sensor for a while?
Thx
Ralph
Hello, yes I think it's enough, in fact there's much more ventilation than in many commercial sensors which only have a small hole. But it's a good test to make, I'll try to compare to a sensor out of it's enclosure to see if there's significant difference or delay.
@Samuel235 said in Homini AC Powered Relay (2) Module:
OMRON G3MB-202P
Okay I'm trying to help you with the fuse component.
I found a datasheet for the OMRON G3MB-202P. And there are enoght information to be known for fuse selection.
I try to calculate it here (and i will try it with my bad English ).
The most important information is the melting integral.
The Melting integral has A²s as unit. So this means the maximum current for a time can exists without damaging the device. For further information look at wikipedia.
So we need any further information about:
the protection which is present before (the typical circuit protection in private houses)
the melting integral from the device which we want to protect
the maximum voltage
the maximum switching current
the breaking capacity
Inrush current for the switched devices (we can't know)
Typical values for an automatic circuit breaker in private houses are:
from 25 to 100 A²s
230 V AC
16 A
So this protection isn't good enough for our relay. The relay have these values:
230 V AC
2 A maximum switching current
I²t value (melting integral): 4 A²s
the allowed inrush current over a small time is higher than the melting integral. It is a bit confusing i think, but if we calculate the protection for the given melting integral and it's fine. So we can define the parameters for the client (switching site of this application here)
The fuse have to be:
I²s value higher or equal than the I²s value from the existing protection
rating voltage over 230 V AC
rating current 2 A or lower (because 2 A is the maximum at 25 °C, for 40 °C it is about 1.6 A)
a maximum switching time of 1 second at 2 A or lower time with higher current but below 4A²s! To calculate use the switching time from the fuse datasheet an multiply it two times with the given current for this switching time.
And i think a fast blow fuse would be the best. There are SMD fuses with 10.1 x 3 mm and 250 V AC available.
If there is no fuse available with the values above, we could combine multiple fuses. A possible solution could be one bigger fuse for both relays and the ac/dc component. And a smaller fuse for the switching site of the relay and the HLK-PM01. But for this it is important that the circuit have only one input for the hot one (L) of 230 V and one output for each relay. In this case we could reduce the big connectors from 6 to 4. Like (L, N, Relay1, Relay2).
And the temperature fuse can work for all components too
So the protection for the primary site of the HLK-PM01 is a problem i think. Because the are no information available about the I²s value from HLK-PM01.
I hope you can understand my English and could follow my explanation?