33 Ohm 5W 5% Fix Wirewound Cement Resistor

If your board needs a 33 ohm 5w resistor, and the old part is a 5W cement part with 5% tolerance, this is the part to order. It is a 33 ohm resistor in a cement body with axial leads, built for power circuits where a small carbon film part would burn out. It fits solar inverters, power supplies, and industrial equipment that need a fixed 33 ohm value at up to 5W. It does not fit jobs that need a different resistance value, a surface-mount body, or more than 5W of power. Check the checks below before you order, so the value, the power, the voltage, and the body all match your board.

This is an original, high-quality part.

What it does

A resistor limits current and drops voltage in a circuit. A cement resistor does that job with its resistance element sealed inside a cement body, which gives high power handling and good heat dissipation for power work. This 33 ohm 5W resistor holds its 33 ohm value within 5%, so a board that calls for 33 ohm gets between 31.35 and 34.65 ohm. The 5W rating is what sets it apart from the small 1/2W resistors used for light signal work only — it can turn far more electrical power into heat without damage, as long as the cooling and the voltage limits below are respected. At full 5W this part carries about 0.39 A (389 mA).

Repair techs use a part like this as a 33 ohm 5w resistor for voltage regulation, where it takes a share of the voltage so the next stage sees the right level, and for current limiting, where a fixed resistance holds current to a safe level. It also fits circuit protection, where a fixed resistance keeps a fault current inside safe limits. It is a cement resistor with axial leads, so it mounts through holes on a board, not on the surface. The cement case is flameproof and fully insulated, which is why this type is used in power circuits.

Key features

• 33 Ohm fixed resistance, ±5% tolerance
• 5W power rating at 40°C ambient
• Wirewound element in a cement body, flameproof ceramic case, fully insulated
• Axial leads for through-hole mounting on PCBs
• Maximum working voltage 350V (see the power-based limit in the checks)
• Temperature coefficient ±100 ppm/°C or ±300 ppm/°C (wirewound — see the gates note)
• Wide temperature range: −55°C to +155°C
• Body about 22 mm long × 9.5 mm wide × 9.0 mm high, 0.8 mm leads

Checks before you order

• Value: your board list must call for 33 ohm. A nearby value is not the same part — if your board needs a different value, stop and check the board list again. A 220 ohm part in the same cement family is a different value for a different job, not a swap for this one.
• Power and heat: the power this part turns into heat must stay at or below 5W, and that 5W counts only up to 40°C ambient — above that, the safe power drops per the series derating curve, so check the derating for your real working temperature. Work out the power from your real voltage and current (power = voltage × current) and keep it inside 5W with room to spare. This part runs hot at full power, so it needs clear air around it.
• Voltage: the voltage across this part must stay at or below about 12.8V in steady use. At this value the power rating is the real limit: at 350V the part would use about 3,712W, far above its rating, even though 350V is the series voltage limit. Work out the voltage from your circuit before you order.
• Tolerance: the real value may sit up to 5% away from 33 ohm. If your circuit needs tighter than 5%, this part is the wrong pick — do not hope the part you get sits near the middle.
• Body and fit: your board must take an axial through-hole cement body. Measure the old part and match it against the holes and the space on your board. The series body for a 5W part is about 22 mm long, 9.5 mm wide, and 9.0 mm high — if your old part is much bigger or smaller, check the board list again before you order. A 0.1 ohm part in the same cement family is a different value for a different job, not a swap for this one.
• Fit for the job: if your circuit only needs a fraction of a watt, this part still works, but it is a big power part — check that the board has room for it. Match the value first, then the power, then the body — a through-hole resistor is the wrong shape for a surface-mount board, even if the value matches.

Specifications

All figures below are from the maker series documents for this resistor family. No figure here was guessed. The maker of the exact part on this page is not stated on the live page, so the publisher should confirm the series figures against the Download file at publish time (see the gates note).

Other names for the same part (good to know)

Shoppers and repair techs call this same part by a few names. 33 ohm 5w is the plain name from its value and power. 33 ohm resistor is the name buyers use with the unit spelled out. 33 ohm 5w resistor is the name buyers use when the power rating matters. Cement resistor is the name for its ceramic case. 33 ohm 5% is the short name that carries the value and the tolerance together. If your board list calls for 33 ohm at 5W with 5% tolerance in a cement body, this page is the right match. Do not judge by size alone — check the value, the power, and the tolerance too.

Frequently Asked Questions

What does 33 ohm mean?

It means 33 ohms of resistance. A resistor marked 33 ohm drops a small amount of voltage at a given current, which is why this low value is used for current limiting and circuit protection rather than voltage division.

What does 5W mean, and what does 5% mean?

5W is the power rating: the most power the part can turn into heat without damage, rated at 40°C ambient, with less allowed as it gets hotter. 5% is the tolerance: the real resistance may sit up to 5% above or below 33 ohm, so between 31.35 and 34.65 ohm.

What is printed on the body of this part?

The photo of the stocked part shows “33 Ohm 5W” printed on the cement body — 33 ohm value and 5W power. That is the print to match. For reference, the same maker’s print style on the 220 ohm part reads “5W 220RJ”, where J is the tolerance code for ±5% — but this part’s photo shows the plain “33 Ohm 5W” print, so check for that wording.

Can I use this part at 350 V if the power is small?

No. At 33 ohm the 5W rating is the limit that matters: it caps the steady voltage at about 12.8V. At 350V this part would use about 3,712W, far above its rating. The 350V figure is the series voltage limit, not a voltage you can use at this value.

How do I fit a cement resistor?

Push the two leads through the matching holes on the board and solder them. The cement body is larger than a small carbon film part, so check the spacing of the holes and the space on the board before you solder, and keep the body clear of parts that cannot take heat — this part runs hot at full power.

What is the price of this part?

Check the live price on the website. The price shown on the product page is the current one.

Use note kept from the old page: this part was listed before as a high-power component designed for efficient energy dissipation in solar inverters and other electronic applications, built with a durable cement casing for excellent thermal resistance and stability, with wirewound construction for handling high power loads, ideal for voltage regulation, current limiting, and circuit protection, with 5W power capacity and 5% tolerance for consistent and reliable performance, for demanding environments where heat dissipation matters, with a fixed resistor design for stable resistance over time and reduced fluctuation, with a cement resistor body for durability, resistance to harsh conditions and prolonged use, used in solar inverters, industrial controls, and power supply circuits as a vital component for efficient power regulation, a ceramic power resistor of 5 watts and 5% tolerance, with wire wound resistors widely used in air conditioners, computers, televisions, and printed circuit boards, made of high-quality ceramic, cement, and metal, good explosion proof, complete insulation, good for PCB — and that use still stands.