Custom request from Czech Customer regarding N4DSB03 on 9th Jun2025
Hello
Here are the questions to modify the layout of the N4DSB03 board:
1)We are used to connect temperature sensor via the 3-pin connector with 2.54 mm pitch:
so that final look would be:
Of course the board can have both holes: holes with 4 mm pitch and holes for 2.54 mm pitch for use with both connector types.
2)Instead of PWR LED, please use plated holes for 2-pin connector 2.54 mm pitch for connecting
“external” LED:
3)Could have holes 3.2 mm for mounting to the base? Similar to the picture?
Specifications for new module QTx6 (1x Digital Input plus 1x temperature input DS18B20)
· Input voltage 12 VDC (in the range at least 9 – 15 VDC, the bigger the range, the better). Of
course, the lowest possible power consumption.
· Reverse polarity protection
· RS485 port. Overvoltage protection
· Connectors for power input and RS485 port similar as for N4DSB03 but with 5 mm pitch
· 3.2 mm holes for fixing the PCB to the base with the pillars
and for attaching a 2 pcs of DIN rail brackets (are you able to deliver suitable rail brackets?)
· 1 temperature input for DS18B20 temperature sensor. 3-pin connector
Wiring as described in the picture.
· The temperature input should be short-circuit proof. Certainly a short circuit between any
wires must not cause the communication on the RS485 line to be blocked.
· 1 digital input for voltage free contacts, e.g. for relay switch contacts. In that case it cannot
measure only voltage on high impedance input, but it should measure the current presence.
So that it will not measure every spike from interference on the DI line.
· The DI should be resistant to disturbances on the supply line and resistant to surge spikes
that may occur on supply wires routed in parallel with wires from power contactors.
The purpose of the digital input is not to measure the highest possible switching frequencies,
but rather to indicate occasional switching/running of the machine.
· Use the same terminals for the DI as for the power terminals.
· 2-pin connector for external LED (can be signed ACT like Activity) that will lit (or blink) in case
there is active communication with this module and that can shortly lit in case power is
connected).
This LED should also indicate that the module is energized by blinking briefly every 5 seconds
or so (instead of the LED marked PWR staying on permanently). In this case the LED marked
PWR is not needed. The reason for this is to keep power consumption as low as possible.
· free area (white background) on the PCB where the current module address will be marked
with a marker.
· printed model identification “QTx6”
Firmware
· Register address for temperature input and digital input should be close together (or directly
next to each other) so the temperature and DI status can be read with one command
· Counter: the module could be able to read pulses on the digital input (and as I said, no high
frequencies are required. It's only about switching the machine, so the ability to read at 1
pulse/second would be fine).
· So the register would be a numeric value for the number of switches on DI.
· This register could be read without erasing the contents of the register.
· And an instruction to write the value of N to another register would cause the value of N to
be subtracted from the number of pulses/switches. So if the pulse register had an M value,
after writing the N value, the counter would have an M-N value. If N value is higher or equal
to M value, the counter will be cleared.
Before preparing the prototype, send me please PCB layout, so I can check if there is no some
problem or collision.
Of course improvements in functionality that I forgot to emphasize here are welcome.
Answer :
Regarding DI, we can only do this and cannot realize more functions: NPN isolated input, when there is a signal input, the collection value is 1, when there is no signal input, the collection value is 0
Question
isolated input is OK. Will it be also blocked against spikes and disturbances? So the question is if DI will contain some LC or RC filter on the input to efficiently filter spikes on input?
Answer :
The software will process it. The collected value is the filtered value.
Question :
And one more technical question: if it is impossible to implement counter function, could it be possible to have register indicating that change occurred on digital input? More detailed: program will read status of DI. It is OFF. After 1 minute it will read the status again and it will be again OFF. And it will not know that meantime the DI was switched ON for 10 seconds.
Answer :
Is this OK? Add an input count register to indicate the number of input pulses, which will be reset to 0 after being read. For example: The first time the input count register is read, the register becomes 0, and then there are 3 pulses greater than 300MS, then the second read data is 3, and then the register will be reset to 0.
We can do as he asks:
“Firmware
· Register address for temperature input and digital input should be close together (or directly
next to each other) so the temperature and DI status can be read with one command
· Counter: the module could be able to read pulses on the digital input (and as I said, no high
frequencies are required. It's only about switching the machine, so the ability to read at 1
pulse/second would be fine).
· So the register would be a numeric value for the number of switches on DI.
· This register could be read without erasing the contents of the register.
· And an instruction to write the value of N to another register would cause the value of N to
be subtracted from the number of pulses/switches. So if the pulse register had an M value,
after writing the N value, the counter would have an M-N value. If N value is higher or equal
to M value, the counter will be cleared.”
（sample shipping + bulik order shipping ) 30%prepaid and we will send sample after 4weeks ,
bulk production shipped 4 weeks after 70% payment done
PCB layout confirmation :