SMD code 51Z
Marking codes are not standardised, and the same code is reused by unrelated makers for unrelated parts. Below is every part in our tables printed with it, and any printed with a code that is easy to misread as it, from the manufacturers' own marking tables and published code lists.
51Z on a chip resistor
0.332 Ω
0.332 Ω resistor, 1%
EIA-96 precision code: 51 selects 3.32 from the E96 series and Z multiplies by 0.1. These are 1% parts.
Check it with a meter
Lift one end and measure across it. A good one reads 0.332 Ω within 1%. Measuring it in circuit reads the parallel combination of everything around it, which is almost always lower, never higher: well above 0.332 Ω on the board is a fault. Open, or well above 0.332 Ω, means it has failed: burnt, cracked or corroded. That does not change what to fit: the marking still says 0.332 Ω. A burnt resistor usually means the part it feeds drew too much, so find that before fitting a new one.
On a transistor or diode body (SOT-23, SMA, SOT-23-5), 51Z is a part code instead. Those parts are listed below.
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The only part printed 51Z in our tables
BZX78-C51
- What it is
- Not recorded
- Maker
- Nexperia
- Package
- SOT-89
- Pins
- 3
- Details
- equivalent BZX87C51
- Source
- Published code list
Is it dead?
Diode range and ohms range, part lifted.
Working, it reads
Depends on what it is. The datasheet, or an identical part, says.
Dead, it reads
- Between two pins, the same reading both ways, near 0 V with a continuous beep: shorted.
- Open between every pair of pins: failed open, or a part that reads open when working.
- On the board
- this is a first look only: the meter reads every path between those pins, and a short can be a neighbour. Lift one leg before you condemn it.
- Compare:
- If an identical part sits elsewhere on the board, measure it the same way: that is what this one should read.
A dead part still carries its marking. A short or an open says it has failed, not that it is a different part.
Was it this one?
Printed with a code easy to misread as 51Z
One character differs, and it is one that is easy to confuse under a lamp. Each code has a page of its own.
Did you find your part?
Open this in the search to correct a character or try another package.