Balanset-1A: Kit, Specs, Connection

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Package contents (Full Kit)

• Measuring unit (2 vibration channels + tachometer channel), USB-powered from the laptop
• 2 vibration sensors (accelerometers) on magnets, 5 m cable (up to 10 m to order)
• Laser tachometer (optical sensor) with a magnetic stand
• Electronic scales (up to 500 g, 0.1 g steps)
• Reflective tape for the mark
• Software on a USB stick
• Plastic case

OEM version is the same but without the case, magnetic stand and scales. A laptop/tablet is not included.

Main specifications

Practical limits:

• below ~300 rpm balancing is hard, below 150 practically impossible (weak sensor signal);
• early bearing diagnostics (envelope method) is not possible — it needs sensors from 10 kHz up, the stock ones work to 550 Hz. Basic defect frequencies (BPFO/BPFI) can still be seen in the spectrum;
• very light rotors (tens of grams) are borderline; resolution down to 0.02 mm/s is achieved by increasing the number of averages.

Vibrationssensorer

• Type — accelerometers (ADXL335-based) outputting vibration velocity. They need power from the unit — hence the three-wire shielded cables.
• The measuring axis runs along the magnet (perpendicular to the mounting face). Mount the sensor so its axis points radially (across the axis of rotation), usually horizontally on the bearing housing. Mounting “on the end face” (axial direction) is a classic mistake that stops the balancing from converging.
• X1 → plane 1, X2 → plane 2. Don’t swap the channels: swapped sensors “flip” the angles.

• The cable is the weak spot: a sensor dragged into the rotor usually has its cable ripped out. Route the cables so they can’t get wound in.

• Sensor service life is 5–7 years or more; no annual calibration required.

Laseromdrejningstæller

• Mounts on the magnetic stand and shines at a Reflekterende mærke (a piece of tape from the kit) stuck on the rotor.
• Gives the device the RPM and the reference pulse for phase. One pulse per revolution = one mark.
• Stick the mark on the hub/shaft, not on a blade: shiny blades, pulley holes and weld seams cause false triggers (details in chapter 08).
• The most fragile part of the kit — protect it from drops and from having its cable dragged into the rotor.

Calibration coefficients — don’t lose them!

Every kit has its own channel sensitivity coefficients (typically values in the 12–25 range). They are recorded:

• on the sticker on the bottom of the measuring unit,
• on the box,
• in a file on the stock USB stick (econfig / ebalan.cfg).

They are entered in the software: F4 – Settings. After reinstalling or updating the software the coefficients must be written down beforehand and re-entered — otherwise the device will show wrong vibration values. Don’t throw the box away until you’ve copied the numbers.

Connection — a quick checklist

1. Sensor 1 (channel X1) — on the plane-1 support; sensor 2 (X2) — on the plane-2 support. Sensor axis radial.
2. Tachometer on the magnetic stand, beam on the mark, the stand must not vibrate.
3. Tighten the connectors: a loose connector nut picks up 50 Hz hum; a bad contact makes a sensor “read zero”.
4. Unit to laptop via USB. Start the software, open Vibrometer mode and confirm that RPM reads correctly and amplitude and phase are stable.

Quick sensor self-test

If you suspect a sensor:

• in vibrometer mode tap/shake the sensor lightly — the reading must respond;
• put both sensors side by side on the same surface — readings should be close;
• “zero” readings (0.01) almost always mean a broken wire or a loose connector contact, not a dead sensor.

Tachometer connector X1 pinout (for DIY hookups)

The actual level at the connector is ~3–5 V. Instead of the tachometer you can feed an encoder index pulse (1 pulse per revolution), but encoder marks are very narrow — the device may miss them without a firmware modification. Third-party sensors (unpowered piezo) are not directly compatible with the stock inputs.