200 µF 250VAC Cylindrical Start Capacitor for Single-Phase Compressor Motor

A problem you have already faced

• The compressor struggles to start or does not start at all — the motor hums but does not turn
• Thermal protection trips at every start — a sign of uncontrolled inrush current
• After replacing the capacitor with a visually similar one the motor burned out — a run capacitor was installed instead of a start capacitor
• Finding the exact part is difficult: manufacturers often show only capacitance and voltage on the label, not the type
• The 2-4 kW compressor starts increasingly hard as the capacitor ages

A worn or incorrectly chosen start capacitor does not stop the compressor immediately — it destroys it slowly, through hundreds of hard starts that burn the winding insulation.

What is the 200 µF 250VAC capacitor: breakdown and operating principle

200 µF — high capacitance, required for maximum starting torque. In 2-4 kW motors, inrush current is 5-7 times the rated value — the capacitor creates the phase shift needed to overcome load resistance at start.

250VAC — working voltage of a start capacitor. It is intentionally lower than run capacitors (400-450VAC) because the start capacitor is in circuit for only 2-3 seconds per start, not continuously.

CBB65 — construction type: metallised polypropylene film capacitor in an aluminium case. Self-healing: at a micro-breakdown point, the surrounding metal film evaporates and isolates the fault — the capacitor survives.

Critical warning: The 200 µF 250VAC start capacitor must not be used as a run capacitor. Connected permanently it will overheat and fail within minutes, risking motor damage.

Technical specifications

Expert tip: When replacing, always read the label on the old capacitor: if it shows ‘S’ or ‘Start’ — it is a start capacitor (250VAC). If it shows ‘R’ or ‘Run’ with 400-450VAC — it is a run capacitor. Mixing the two types is the most common mistake in self-service repairs.

How to choose the right start capacitor: a 5-step process

1. Identify the type of the existing capacitor. Read the label: ‘S’/’Start’ = start type (250VAC, high capacitance). ‘R’/’Run’ = run type (400-450VAC, low capacitance). Always replace like-for-like.
2. Check the capacitance (µF). Must match exactly the value on the old capacitor label or the motor data sheet. Acceptable tolerance: ±10% from the rated value.
3. Check the voltage (VAC). The replacement capacitor must have a working voltage at least equal to the original. A 250VAC capacitor may be replaced with a 300VAC one — not the other way around.
4. Check the physical dimensions. Diameter 50 mm, height 95-105 mm — standard for 2-4 kW motors. Confirm it fits in the compressor’s electrical enclosure.
5. Check the terminal type. Faston 6.3 mm — standard for this series. For screw-type or different terminals, consult Acvatron SRL for adapters.

Why Acvatron SRL — 5 compelling reasons

1. Correct type identification: start vs. run

Acvatron SRL supplies capacitors with clear type labelling (start/run). Eliminate the risk of confusion that leads to motor failure. If in doubt, our specialists identify the correct type from the compressor make and model.

2. Verified parameters: 200 µF ±5%, 250VAC

Every batch is accompanied by conformity certificates to IEC 60252-1. The ±5% tolerance guarantees stable starting torque at every cycle, without degradation of characteristics over time.

3. Self-healing technology — extended service life

The metallised polypropylene film dielectric self-repairs after the micro-breakdown points that are inevitable under high inrush current. This significantly extends service life compared to cheap electrolytic alternatives.

4. In stock in Chisinau, same-day dispatch

CBB65 200 µF 250VAC capacitors are held in stock. Your compressor will not be idle more than a day for lack of a spare part.

5. Technical support for part identification

Not sure which capacitor you need? Acvatron SRL specialists identify the exact part from the compressor make and model or a photo of the old capacitor — at no extra charge.

Application areas

Expert opinion

Vitali Bolucevschi, mechanical engineer, Acvatron SRL — 18 years in compressor and pump servicing:

The 200 µF 250VAC capacitor is the part customers misidentify most often. Someone comes in and says ‘I put the same one in, 200 µF, but a different one, and everything burned’. You look — they installed a run capacitor instead of a start capacitor. Visually they are identical, but the operating mode is fundamentally different. The 250VAC start capacitor is in circuit for a maximum of 2-3 seconds per start — that is exactly why it handles a large capacitance at a lower voltage. If you have a heavy-duty 2-4 kW compressor that is starting hard or tripping the overload, replace the start capacitor and do not delay: every hard start takes several operating hours off the winding life.

Standards: IEC 60252-1 (start capacitors for single-phase motors), IEC 60068-2 (environmental tests), protection class IP54 per IEC 60529.

Handling common objections

“I can find a cheaper capacitor on an import website”

A CBB65 capacitor without an IEC 60252-1 certificate may have a capacitance tolerance of ±20% or more — starting torque will be unstable and the motor will continue to start hard. Moreover, a dielectric without self-healing degrades after the first few hundred starts. The price of a capacitor is a fraction of the cost of rewinding a motor.

“I have a 200 µF run capacitor — can I use it?”

No. The run capacitor is designed for continuous circuit operation and has a different dielectric optimised for sustained load. Under start conditions (current 5-7 times rated) it will overheat and fail within minutes. Use only capacitors marked ‘Start’ or ‘S’ at 250VAC for the start circuit.

“I am not sure which capacitor my compressor needs”

Contact Acvatron SRL with the compressor make and model or a photo of the old capacitor. Our specialists identify the exact part in 10 minutes, at no consultancy charge.

Frequently asked questions

How do I tell a start capacitor from a run capacitor?

Key features of a start capacitor: high capacitance (100-500 µF) at a relatively low voltage (250-300VAC) and an ‘S’ or ‘Start’ marking on the body. A run capacitor has low capacitance (2-80 µF) at a higher voltage (400-450VAC) and an ‘R’ or ‘Run’ marking. On the wiring diagram, the start capacitor is connected through a centrifugal switch or timer relay.

Can I use the 200 µF 250VAC capacitor as a run capacitor?

No. The start capacitor is designed for a maximum of 2-3 seconds per start cycle. Connected permanently it will overheat and fail within a few minutes of motor operation. This is a direct violation of operating conditions and will damage both the capacitor and the motor.

Why does the compressor still not start after I replaced the capacitor?

If the new capacitor is correctly chosen but the problem persists, check: the centrifugal switch (it may not be opening the start circuit at the right time), the start winding condition (open circuit or inter-turn short), and the supply voltage at the moment of starting (a drop below 200V will prevent starting even with serviceable components). Acvatron SRL specialists can help diagnose the problem.

How often should the start capacitor be replaced?

Start capacitor service life depends not on running time but on the number of starts. Under intensive use (15-20 starts per day), a preventive capacitance check is recommended every 12-18 months. The sign of capacitance loss: the multimeter reading drops by more than 10% below the rated value.

Take the next step right now

1. Call or message us on WhatsApp/Viber — Acvatron SRL specialists will identify the exact capacitor for your compressor make and model in 10 minutes.
2. Receive stock confirmation and pricing on the day of your enquiry.
3. Collect the part from our Chisinau warehouse on the same day or receive next business-day delivery within Moldova.

Acvatron SRL — spare parts and components for compressors and pneumatic equipment in Moldova.