23
votes
Accepted
What is this "/|\" symbol on the enclosures of various appliances?
The Broad Arrow (aka 'pheon') indicates that the item in question was once (British) Government property - a Crown asset.
22
votes
What is ohm joules (ΩJ) unit used for?
That's not J for joules. It's probably J for 5% tolerance. The component is just a 10 mΩ resistor with a 5 W rating.
- 7,948
20
votes
Accepted
Why datecode is SO IMPORTANT to chip manufacturers?
Date codes (and sometimes batch codes which are usually on the packaging) are important for traceability both for the device manufacturer and the customer.
In safety critical applications (such as ...
- 22.5k
18
votes
PCB Logic Board Reference Designator "E"
IEEE Std 315 suggests that you use "TP" for testpoints. The single letter "E" can be used for many things, including "circuit terminal", "electrical contact", ...
- 31.6k
18
votes
What is ohm joules (ΩJ) unit used for?
"J" means a resistor value tolerance of +/- 5% as per this site.
The resistor in question has a value of 10 milli-ohms (\$m\Omega\$).
It also applies to capacitors as per this wiki site: -
- 467k
17
votes
Accepted
PCB Logic Board Reference Designator "E"
It's a pad for a flying probe test (which happens at assembly and you can see indentations from a probe or meter, if this is a production board then it's probably a flying probe test point).
Flying ...
- 87.2k
14
votes
What do multiple contact ratings on a relay represent?
Yes, it can support lower voltages (e.g., 24VAC), so long as the current is less than 15A.
Different regional standards, different ratings. The first "10A/250VAC" is the TÜV rating (EU ...
- 56k
11
votes
Accepted
Need help identifying the value of a tantalum capacitor marked 226C
"226" = "22" followed by 6 zeros, in pF. 22,000,000 pF = 22µF
"C" = 16V
See: https://www.electronics-notes.com/articles/electronic_components/capacitors/capacitor-codes-...
- 20.1k
10
votes
Accepted
Is this capacitor marking in pF or µF?
That is a ceramic disc capacitor, 47 pF.
Here's a datasheet for a typical capacitor of this type:
https://www.vishay.com/docs/28515/sseries.pdf
A good clue: The two capacitors, crystal, and resistor ...
- 15.2k
10
votes
What do multiple contact ratings on a relay represent?
It states "15A 125VAC". Does that mean it will support any voltage up to 125VAC, including 24VAC?
Yes.
Is there a formula I can use to calculate the maximum amperage that can be drawn on ...
- 7,948
8
votes
SMD diode identifying marking 96
Rohm RB055LAM-60 Schottky Barrier Diode in SOD128 Package with marking code 96.
The how:
Firstly, what package is the diode in - knowing the package limits the search massively. In this case it's a ...
- 68.8k
8
votes
Having trouble identifying value of inductor, what is its inductance?
From the photo it looks like 10uH +/-10%.
The band color appears to be silver (not grey/gray), plus 80uH would not be an E12 value (8.2uH would be) and brown is a rather unlikely tolerance (1%) for ...
8
votes
PCB Logic Board Reference Designator "E"
Test point? That's the designation we use for such things.
Edit 1
Note, we also use "E" for the uses Elliot mentioned in his comment. I'm gonna venture a guess that someone along the way ...
- 10.9k
8
votes
Is this capacitor marking in pF or µF?
Encoding for Ceramic Capacitors
Ceramic capacitors encoding consists 1-3 digits.
If the capacitor code consist only 1 or 2 digits, it is simply their capacitance value in PicoFarads (pF). For example ...
- 4,550
7
votes
Accepted
Why are capacitors usually marked on the negative terminal, not positive?
Why are capacitors usually marked on the negative terminal, not
positive?
Here some polarized capacitors: -
Now you tell me which is the dominant polarity marker?
- 467k
7
votes
Accepted
How to identify SMD device marked LEFBV?
It's an IRLML0060TRPbF N-channel MOSFET
Maybe, anyway.
From the International Rectifier (now Infineon) datasheet, it matches your pinout:
And the markings seem very familiar, too:
L̲...
- 2,606
7
votes
Accepted
MKT capacitor with ohm value on case markings
I would like to provide an alternative answer, as to me it makes no sense to have a complex impedance of 0.25J + 200 Ohms printed on a capacitor-looking device, when I know that components that are ...
- 165k
7
votes
Accepted
Unknown SMD Component
The usual search from s-manuals (https://www.s-manuals.com/smd/aa) didn't bring useful results.
The part looks like a low voltage op amp judging from the schematic. The right-hand side sub-circuit ...
- 38.1k
7
votes
Unknown SMD Component
This is roughly how that circuit can be re-drawn:
simulate this circuit – Schematic created using CircuitLab
And here is it re-drawn to be easier to follow:
simulate this circuit
7
votes
Is this capacitor marking in pF or µF?
That is a ceramic disc capacitor, normally you would have three figures on it, and the value is in pF; 470 means 47 x 10^0 = 47 pF, 102 = 10 x 10^2 = 100 pF and so on.
I suppose in this case they just ...
- 16.5k
6
votes
Accepted
5
votes
Accepted
Capacitor Numbers, What do these markings mean?
I would agree its a 330uF 16V capacitor.
The 282 appears to be a production or lot code.
The information is found in datasheets, so you would need to determine the manufacturer and series to be sure....
- 363
5
votes
Accepted
What do 'L2' or 'L3' marking codes on electrolytic capacitors mean?
Probably (German industry?) standardized case size codes.
Kemet lists these sizes:
5
votes
What do multiple contact ratings on a relay represent?
Yes. And, both the voltage and current ratings are maximums that are independent of each other. For a 1 VAC signal, the max current still is 10 A.
The symbols to the left are the logos for safety ...
- 22k
5
votes
Color Code for Fusible or Flame Retardant Resistors: Data Sheets, Standards?
Overview (details and sources follow below)
Body Color
Fifth Band
Manufacturer
Type
Material
Fusing
Non-Flammable
Grey
Violet
Vishay BC
NFR25
Metal Film
Yes
Yes
Grey
White
Vishay BC
NFR25H
Metal ...
- 18.5k
4
votes
Accepted
SMD transistor marking
It is a date/manufacturing code. Does not change pinout in any way.
Look at this datasheet:https://www.mouser.com/ds/2/308/MMBT4401LT1-D-108598.pdf
- 1,769
4
votes
Accepted
SMD Component Identification 6 pin with diode properties
"K5" identifies the PESD5V0S4UD, a 5 V ESD protection diode array made by Philips NXP Nexperia:
- 19.7k
4
votes
SMD LED polarity marking: is the cathode marking standardized?
I believe that PCB manufacturers are aware of the fact that surface mount LED can have the tab on the Anode side. I have worked before with several manufacturers and they have always asked about the ...
- 447
Only top scored, non community-wiki answers of a minimum length are eligible