Before you balance: make sure unbalance is really the dominant fault. The vibration should be dominated by the 1× (running-speed) component; check that mounting bolts are tight and there is no looseness, rule out shaft misalignment, and verify the machine is not running close to a structural resonance — use the software's 衝擊測試 to find the natural frequencies. Balancing will not cure looseness, misalignment, or a resonance problem.
In the software, open the balancing wizard — F3 - Two-plane （或 F7 - Balancing) — and start on the Run 0 - Initial tab. Start the rotor and bring it to stable operating speed. The instrument measures vibration amplitude (mm/s) and phase angle (°) at both sensors simultaneously. This is the 基線 ——轉子在處理前的「病態」。記錄數值並停止機器。
停止轉子。將已知質量的 試重 of known mass at an arbitrary angular position in Plane 1. Mark this position clearly — it becomes your 0° reference for angle measurement later. Enter the trial weight Mass, g 與 Radius, mm in the software's Trial weight group — without the mass entered, the program can only report the correction as a percentage of the trial weight. Switch to the Run 1 - Trial Pl.1 tab, restart the rotor and record vibration at both sensors. The instrument now knows how the rotor's vibration field changes when mass is added in Plane 1.
Field tip: Use a bolt with a washer clamped to the rotor rim, or a hose clamp with a nut for quick attachment. The trial weight should produce a measurable vibration change (20–30% amplitude change or 20–30° phase shift at either sensor).
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試重應該有多重？ 使用經驗公式： Mt = Mr × Ksupport × Kvibration / (Rt × (N/100)²) 其中 Mr = rotor mass (g), Ksupport = support stiffness coefficient (0.5–5.0, use 3 for standard pedestals), K振動 = vibration level coefficient (0.5–3.0, use 1.0 for normal vibration of 5–10 mm/s), Rt = 安裝半徑（cm），N = RPM。或使用我們的 online trial weight calculator — 輸入您的轉子參數，即可立即獲得建議質量。
4
將試重移至校正平面 2（運轉 2）
Stop the rotor. Remove the trial weight from Plane 1. Attach the same trial weight (or one of similar known mass) at an arbitrary position in Plane 2. Mark this second reference point. Switch to the Run 2 - Trial Pl.2 tab, restart and record vibration at both sensors. Now the instrument has the complete influence coefficient matrix — four complex coefficients linking unbalance in either plane to vibration at either sensor.
現場提示：若在校正平面 2 使用不同質量的試重，請在軟體中輸入正確數值——數學運算會自動調整。
5
Calculate Correction Weights
The instrument solves the influence coefficient equations and displays the Correction mass (g) 與 Angle (°) for Plane 1 and Plane 2. The angle is measured from the trial weight position in the direction of rotor rotation. In the Correction method group you choose Add mass (weld or bolt a counterweight) or Remove mass (drill or grind material). The displayed angle is always the angle you actually work at: with Remove mass selected the software has already added 180° to the computed angle, so drill or remove exactly where it indicates — do not add another 180°.
6
安裝校正配重
Remove the trial weight from Plane 2. Fabricate or select correction weights matching the calculated masses. Install each correction weight at the same radius as the trial weight — the calculated mass is valid only at that radius. If you must use a different radius, enter both radii in the software so it recalculates the mass. Measure the angle from the trial weight reference mark in the direction of rotation. Attach the correction weights firmly — welding, hose clamps, set‑screw weights, or bolts depending on the machine type and speed.
Field tip: If you cannot place a weight at the exact angle (e.g. only bolt holes available), use the Weight Installing Method setting — Free positions, Fixed positions, Circular groove, or Drill. With Fixed positions the instrument decomposes the correction vector into two components at the nearest available positions.
7
驗證平衡（檢查運轉）
Restart the rotor and record the final vibration. Compare against the initial baseline and against the ISO 21940‑11 tolerance for your machine class — enter the tolerance in the Balancing tolerance, g*mm field, or press the ISO 1940... button to calculate it from the G‑grade, rotor mass, and RPM (divide the g·mm result by the correction radius to get grams). If vibration is within specification, you are done. If not, the instrument can perform a 修補運轉 on the Run T - Trim tab — it uses the existing influence coefficients to calculate a small additional correction without new trial weights.
The trial weight must be heavy enough to produce a noticeable vibration change, but light enough not to overload bearings or create a dangerous condition. The standard empirical formula accounts for rotor mass, correction radius, operating speed, support stiffness, and the measured vibration level:
Values shown assume Ksupport = 3 (standard bearing pedestals) and K振動 = 1.0 (normal vibration of 5–10 mm/s); scale accordingly for other support and vibration conditions.
實用建議：驗證響應
The formula gives the minimum trial mass that should produce a measurable response. After the trial run, check that the phase shifted by at least 20–30° and the amplitude changed by 20–30%. If the response is too small, double or triple the trial mass and repeat. At very low RPM (< 500), the formula may yield impractically large values — instead size the trial weight so that its centrifugal force is about 10% of the rotor weight: m = 0.1 × Mr × 9.81 / (ω² × r), with m and Mr in kg, ω in rad/s and r in meters.
Balanset‑1A result screen: the software calculates the correction for each plane and displays it on a polar chart. The blue vector with the green end marker points at the correction weight position; the red rings are the amplitude scale. Here the correction mass is shown in % of the trial weight because the trial mass was not entered — enter Mass, g in the Trial weight group to get grams and residual unbalance in g·mm.
如何測量角度
參考點（0°）： 您放置試重的角度位置。在試運轉前，請在轉子上清楚標記該位置。
測量方向： 始終沿轉子旋轉方向。
讀取角度： the result window shows the Correction mass 與 Angle for each plane. From the trial weight mark, count that many degrees in the rotation direction — that is where the correction weight goes.
若需移除質量： select Remove mass in the Correction method group — the software adds 180° to the computed angle automatically, so drill or grind exactly at the displayed angle.
將配重拆分至固定位置
When the rotor has pre‑drilled holes or fixed mounting positions (e.g. fan blade bolts), you may not be able to place a weight at the exact calculated angle. In the Balanset‑1A software this is handled by the Weight Installing Method setting, which offers four modes: 自由位置, 固定位置, 圓形溝槽，以及 Drill (material removal, with drilling-depth calculation). With Fixed positions you enter the angles of the two nearest available positions, and the software decomposes the single correction vector into two smaller weights at those positions. The combined effect matches the original vector.
Extremely heavy rotors (200–1,000+ kg). Trial weights are large — typically 0.3–3 kg by the formula (a 1,000 kg rotor at 600 RPM needs ≈ 3.3 kg). Low RPM means large permissible unbalance — but impact loads and bearing cost still justify balancing.
Ultra‑high speed demands G 1.0 or tighter tolerance. Material removal by grinding — no welded weights at these speeds. Note the instrument limits: the Balanset‑1A covers 250–90,000 RPM and 5–1,000 Hz, with best sensor accuracy below ~550 Hz — service speeds beyond that range are outside its measurement envelope.
配重安裝方法
方法
固定方式
最適用於
限值
Welding
鋼製墊圈或板片點焊於轉子輪轂
粉碎機、破碎機、重型工業轉子
永久性。若無特殊焊條，不可用於鋁材或不鏽鋼
螺栓與螺母
螺栓穿過預鑽孔並使用防鬆螺母
風機葉輪、飛輪、聯軸器凸緣
需使用現有孔洞或新鑽孔
軟管夾
不鏽鋼軟管夾夾住配重
現場的軸、滾輪、圓柱形轉子
臨時性或半永久性。需確認夾緊扭矩
頂絲夾持式
預製夾持式配重（類似輪胎配重）
風機葉片、薄輪轂、輕型轉子
質量範圍有限。高轉速時可能滑動
黏合劑（環氧樹脂）
配重黏貼於表面
精密轉子、潔淨環境
需清潔乾燥之表面。溫度限制約 120°C
材料去除
在重側鑽孔或研磨去除材料
渦輪增壓器、高速主軸、葉輪
永久性且精確，但不可逆。當增加配重不安全時使用
現場平衡常見錯誤
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錯誤
後果
修正方法
1
感測器安裝於護罩或蓋板上
蓋板的共振會扭曲振幅與相位讀數 → 導致校正錯誤
務必安裝於軸承座的金屬表面
2
試重過輕
相位與振幅變化處於雜訊範圍內 → 影響係數不可靠
確保至少一個感測器的振幅變化達 20-30%，或相位偏移達 20-30 度
3
運轉間的速度變化
1× 振動隨 RPM² 變化 — 即使 5% 的速度變化也會破壞資料
使用轉速計進行精確的 RPM 追蹤。等待轉速穩定
4
Leaving the trial weight on without telling the software
Correction calculation is skewed by the unaccounted trial weight → result is meaningless
Remove the trial weight before installing correction weights — or tick Leave on rotor in the Trial weight group so the software accounts for it
5
混淆校正平面 1 與校正平面 2
校正配重安裝於錯誤的校正平面 → 振動增加
清楚標示感測器與校正平面。感測器 1 → 校正平面 1，感測器 2 → 校正平面 2
6
測量角度與旋轉方向相反
Correction goes 360° − f instead of f → the weight lands mirrored about the reference mark — up to 180° away from the correct position
Trial mass note: with Ksupport = 3 and K振動 = 1 the trial weight formula suggests only ≈ 37 g for this rotor — the formula result is a minimum, and higher Ksupport/K振動 factors call for heavier weights. The 500 g weight used on this job was well above that minimum; the >60% amplitude response confirmed a valid trial, which is the criterion that actually matters.
感測器 2（綠色）： Install closer to the rear of the fan (Plane 2 side).
Plane 1 (red zone): Correction plane on the impeller disc, closer to the front.
Plane 2 (green zone): Correction plane closer to the back plate or hub.
Connect both vibration sensors and the laser tachometer to the Balanset‑1A. Attach reflective tape to the shaft or hub for RPM reference.
動平衡校正流程
Start the fan and take initial vibration measurements (Run 0). Install a trial weight of known mass on Plane 1 at an arbitrary point, run the fan, and record the vibration change (Run 1). Move the trial weight to Plane 2 at an arbitrary point, run the fan again, and record (Run 2). The Balanset‑1A software uses all three measurements to calculate the correction mass and angle for each plane.
Correction weights installed on the fan impeller at positions calculated by the Balanset‑1A.
Angle Measurement for Fan Correction Weights
The angle is measured from the trial weight position in the direction of fan rotation — exactly as described in the 校正角度測量 section above. Mark where the trial weight was placed (0° reference), then count the indicated angle along the rotation direction to find the correction weight position.
Typical field balancing setup (illustration): vibration sensors on the machine, Balanset‑1A measuring unit, and a laptop running the balancing software.
Based on the angles and masses calculated by the software, install the correction weights on Plane 1 and Plane 2. Run the fan once more and verify that vibration has dropped to an acceptable level per ISO 21940‑11 (typically G 6.3 for general‑purpose fans). If residual vibration is still above target, perform one trim run.
常見問題
Static balancing corrects unbalance in a single plane — the rotor's centre of gravity is shifted back to the rotation axis. It works for narrow, disc-shaped parts where the length-to-diameter ratio L/D is below about 0.5. Dynamic balancing corrects unbalance in two planes simultaneously, addressing both force and couple unbalance. It is required for any elongated rotor where masses are distributed along the shaft length. A rotor can be statically balanced yet dynamically unbalanced — the couple component is invisible until the rotor spins.
Use the formula: Mt = Mr × Ksupport × K振動 / (Rt × (N/100)²), where M is in grams, R in cm, and N in RPM. Ksupport is the support stiffness coefficient (0.5–5.0: 1 = soft, 3 = average, 5 = rigid) and K振動 is the vibration level coefficient (0.5–3.0, 1.0 for normal vibration of 5–10 mm/s). The goal is to produce at least 20–30% amplitude change or 20–30° phase shift. Or skip the maths and use our online trial weight calculator. At speeds below 500 RPM the formula becomes impractical — instead size the trial weight so its centrifugal force is about 10% of the rotor weight: m = 0.1 × Mr × 9.81 / (ω² × r), with m and Mr in kg, ω in rad/s and r in meters.
Use single-plane for narrow disc-shaped rotors with L/D below about 0.5 — flywheels, grinding wheels, saw blades. Use two-plane for anything longer: shafts, fan impellers, mulcher rotors, rollers, multi-stage pump assemblies. When in doubt, always choose two-plane — it catches couple unbalance that single-plane misses, and only adds one extra measurement run (about 10 minutes).
ISO 21940-11:2016 is the current standard for rigid rotors. It replaced ISO 1940-1:2003. It defines balance quality grades from G 0.4 (gyroscopes) to G 4000 (slow marine diesel crankshafts). Common grades: G 6.3 for fans and pumps, G 2.5 for electric motors, G 1.0 for turbocharger rotors, G 16 for agricultural machinery and crushers. The grade times the angular velocity gives the maximum permissible CG velocity in mm/s — from there you calculate the allowable residual mass at the correction radius.
The instrument calculates the correction angle relative to the trial weight position. Mark where you placed the trial weight — this is your 0° reference. Then measure the indicated angle in the direction of rotor rotation from that reference point. The correction weight goes at the resulting position. If you select Remove mass in the Correction method group, the software adds 180° to the computed angle automatically — drill or grind exactly at the displayed angle. Use a protractor or divide the circumference into marked segments before starting.
Yes — this is called field balancing or in-situ balancing. You mount vibration sensors on the bearing housings, attach a tachometer reference, and run the machine at operating speed. A portable instrument like the Balanset-1A guides you through the trial weight sequence and calculates corrections. Field balancing saves hours of disassembly time, eliminates alignment errors from reinstallation, and balances the rotor under real operating conditions — including the effect of coupling, thermal growth, and actual bearing stiffness.
現場平衡設備
Balanset‑1A is a two‑channel portable instrument that handles single‑plane and two‑plane dynamic balancing, plus vibration analysis (overall velocity, spectra, waveform). It ships as a complete kit:
2 個 MEMS 振動感測器（基於 ADXL335 的加速規），附磁吸座
Laser tachometer (non‑contact RPM sensor) with reflective tape
USB measuring unit (connects to any Windows laptop)
RPM range: 250-90,000. Vibration range: 0.2-80 mm/s RMS. Frequency range: 5-1000 Hz. Phase accuracy: ±1°. Weight splitting, trim runs, tolerance checking, and report generation included in the software. Full kit weighs approximately 4 kg.
13+ years in vibration diagnostics and field balancing. Personally balanced 2,000+ rotors across mulchers, fans, crushers, centrifuges, and combine harvesters in 20+ countries.
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