Case Study: DC24V Medical Bed Electromagnet, 300 g at 5.8 mm and 500,000 Cycles, Sample Approved
Medical Bed Electromagnet: Sample Tested, Test Passed
A medical equipment customer requested a solenoid actuator for a medical bed platform. We supplied a DC24V electromagnet built to their requirement, they tested the sample on their own bench, and the result was a clear pass — with explicit satisfaction from their engineering team. This case explains what the part had to do and what "passed the test" actually covered.
What a Medical Bed Actuator Has to Survive
Medical beds are not a forgiving application. The actuator has to work correctly in situations where a normal industrial solenoid would be allowed to fail occasionally:
- Load holding under a patient. The force has to be available at the working stroke, not just at zero gap — and it has to be repeatable after thousands of operations.
- Extended energisation. In clinical use a nurse may hold an adjustment for far longer than a duty cycle suggests. The part must tolerate it without thermal damage.
- Electrical safety. Anything near a patient bed is judged on insulation and dielectric strength, not only on force.
- Life expectancy measured in years. A bed may actuate several times a day for a decade; the components inside it are expected to outlast the warranty by a wide margin.
The Part We Supplied
| Item | Specification |
|---|---|
| Application | Medical bed electromagnet (medical device / DC micro solenoid) |
| Rated voltage | DC 24 V (working range DC 24 V ±10%) |
| Rated power / coil resistance | 18.48 W at DC24V, coil 31 Ω ±10% |
| Operating cycle | ON : OFF = 0.05 s : 0.15 s; continuous energisation permitted up to 300 s |
| Force | ≥ 300 g at 5.8 mm stroke |
| Operating temperature | -20 °C to +45 °C |
| Relative humidity | 5% to 60% RH |
| Insulation resistance | DC 500 V, ≥ 50 MΩ (coil to bobbin) |
| Dielectric strength | 700 V, 50/60 Hz, 1 s, leakage ≤ 1 mA (coil to case) |
| Service life | Over 500,000 cycles under normal use |
| Appearance standard | No damage, cracks, rust or surface stains |
The Three Numbers That Decided It
≥ 300 g at 5.8 mm. Force quoted at the working stroke, not at zero gap. This is the single most common place where a solenoid specification goes wrong: a supplier quotes holding force at contact, the customer's mechanism works at a 5.8 mm stroke, and the delivered force is a fraction of what was expected. Specifying at the actual stroke removes the argument before it starts.
300 s of continuous energisation. The nominal duty is 0.05 s ON / 0.15 s OFF, but the specification explicitly permits continuous supply for up to 300 seconds. In a clinical setting that allowance matters — a held adjustment should not cook the coil, and the part should not need a driver-side timer to protect it.
Over 500,000 cycles. Five times the life commonly quoted for small solenoids. For a device that actuates several times a day over a ten-year service life, that headroom is the difference between a warranty claim and a non-event.
What the Customer's Test Covered
- Force verification at stroke. Force measured at the 5.8 mm working position, repeated across the sample batch to check consistency rather than a single best-case result.
- Thermal behaviour under extended power. Continuous energisation observed for heat build-up within the housing, confirming the 300 s allowance holds in practice.
- Electrical safety checks. Insulation resistance at DC500V between coil and bobbin, and dielectric strength with leakage held within 1 mA — the checks a medical device approval actually depends on.
- Cycle and functional behaviour. Repeated actuation to confirm the force does not decay and the mechanism still releases cleanly.
- Appearance and workmanship. Inspection for damage, cracking, rust and surface staining as a production acceptance criterion.
The sample passed, and the customer's feedback was straightforward satisfaction with both the performance and the documentation behind it.
Why Medical Customers Ask Different Questions
When the end product is a hospital bed, the purchasing conversation changes. The questions are not "what is the cheapest solenoid" but "what happens at 5.8 mm", "what happens if it stays powered for five minutes", "what is the leakage current", and "how many cycles before the force drops". A specification sheet that answers those four questions in writing is what makes a sample request turn into a supply relationship — and it is exactly the same data we will provide to the next customer with the same application.
Availability
This medical bed electromagnet is available for sampling and series production. Voltage, coil resistance, stroke and force targets can be adapted to your mechanism, and we can support the electrical safety documentation your device approval requires.
Send your actuator requirement — stroke, required force, duty pattern and safety standard — and we will confirm the specification and supply samples for your own bench test.
