What is a UDL variator?
A UDL variator is a stepless mechanical speed controller based on a V-belt and cone pulley principle, designed for direct flange mounting to a standard IEC three-phase asynchronous motor. Speed variation is achieved by adjusting the axial gap between a pair of conical sheaves: as the gap changes, the V-belt runs at a different effective radius, smoothly altering the transmission ratio and output speed.
Compared to planet-disc motovariators (Motovario TXF/S), the UDL is a more compact and economical solution for lower power ranges — from 0.18 to 1.10 kW. Speed adjustment is performed via a handwheel while the motor is running. The output speed varies continuously within an approximately 1:5 ratio (e.g. 200 to 1000 rpm).
Applications — what is it suitable for?
UDL variators are the optimal choice for low-power drives requiring stepless speed adjustment during operation without stopping the machine. Typical applications: small conveyor belts and feeding devices; dosing and portioning machines; small mixers and pumps; food processing and dough-mixing machines; printing and packaging machines (low power); laboratory and medical equipment.
The UDL series is particularly suitable when: required power is up to 1.10 kW; installation space is limited; cost is a decisive factor; ATEX certification or special environments are not required.
Performance data by size
| Type | P1 (kW) | Poles | IEC motor | n2 max (rpm) | n2 min (rpm) | T2 min (Nm) | T2 max (Nm) |
|---|---|---|---|---|---|---|---|
| UDL 002 | 0.18 | 4 | 63 B5 | 880 | 170 | 1.5 | 3 |
| UDL 005 | 0.25 | 4 | 71 B5 | 1000 | 200 | 2 | 6 |
| UDL 005 | 0.37 | 4 | 71 B5 | 1000 | 200 | 3 | 6 |
| UDL 010 | 0.55 | 4 | 80 B5 | 1000 | 200 | 4.4 | 12 |
| UDL 010 | 0.75 | 4 | 80 B5 | 1000 | 200 | 6 | 12 |
| UDL 010 | 1.10 | 4 | 90 B5 | 1000 | 200 | 8 | 12 |
Overall dimensions (mm) and weight
| P1 (kW) | Type | A | B | B1 | C | C1 | D | H1 | H2 | L | M | N | Kg |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 0.18 | UDL 002 | 318.5 | 111.5 | 64 | 3.5 | 6.5 | 11 | 78 | 70 | 140 | 115 | 95 | 3.3 |
| 0.18 | UDL 002 | 318.5 | 111.5 | 64 | 3.5 | 6.5 | 14 | 78 | 70 | 140 | 115 | 95 | 3.3 |
| 0.37 | UDL 005 | 333 | 108 | 71.5 | 3.5 | 8.5 | 14 | 91 | 80 | 160 | 130 | 110 | 4.6 |
| 0.37 | UDL 005 | 333 | 108 | 71.5 | 3.5 | 8.5 | 19 | 91 | 80 | 160 | 130 | 110 | 4.6 |
| 0.75 | UDL 010 | 398.5 | 143.5 | 87.5 | 3.5 | 10.5 | 19 | 107 | 100 | 200 | 165 | 130 | 7.9 |
| 0.75 | UDL 010 | 398.5 | 143.5 | 87.5 | 3.5 | 10.5 | 24 | 107 | 100 | 200 | 165 | 130 | 7.9 |
| 1.10 | UDL 010 | 398.5 | 143.5 | 87.5 | 3.5 | 10.5 | 24 | 107 | 100 | 200 | 165 | 130 | 7.9 |
Note: D = output shaft diameter (mm). L, M, N = output flange dimensions (IEC B5 standard). Two rows per size reflect different shaft diameters (D) available.
Recommended lubricants
| Oil specification | Brand |
|---|---|
| Dexron fluid II | IP |
| A.T.F. Dexron fluid DIII | SHELL |
| A.T.F. 200 RED | MOBIL |
| A.T.F. Dexron | FINA |
| BP Autran DX | BP |
| A.T.F. Dexron | ESSO |
| A.T.F. Dexron | CHEVRON |
| A.T.F. Dexron | AGIP |
All recommended oils are ATF (Automatic Transmission Fluid) type, Dexron II/III class — identical to the recommendation for Motovario TXF 002–010 (ISO VG 32 / ATF Dexron). Widely available from all major suppliers.
UDL vs. Motovario TXF — which variator to choose?
| Criterion | UDL | Motovario TXF/S |
|---|---|---|
| Operating principle | V-belt / cone pulley | Planet discs / Belleville springs |
| Power range | 0.18 – 1.10 kW | 0.15 – 9.2 kW |
| Speed variation ratio | ≈ 1:5 (200–1000 rpm) | ≈ 1:5 (standard) |
| Max output torque | 12 Nm | up to 144 Nm |
| Compactness | More compact | Larger at equal power |
| Cost | Lower | Higher |
| Maintenance | Belt inspection | Oil change |
| ATEX | No | On request |
| Best for | Small drives, limited budget | Medium/heavy drives, all environments |
UDL catalogue
Download PDF ↓FAQ — Frequently Asked Questions
What is the difference between a UDL variator and a Motovario TXF motovariator?
The UDL is a V-belt variator — it adjusts speed by changing the effective radius of the V-belt between conical sheaves. The Motovario TXF uses planet discs and Belleville springs. The UDL is more compact and economical for low power (up to 1.10 kW), but is limited in power and torque range. The Motovario TXF/S covers up to 9.2 kW and is more versatile for demanding applications.
Must speed adjustment be done while the motor is running?
Yes — speed adjustment on UDL variators must be performed with the motor running, via the handwheel. Adjusting a stationary variator is not permitted and can cause damage.
What oil is used in the UDL variator?
ATF (Automatic Transmission Fluid) type, Dexron II/III class. Recommended brands: IP Dexron II, Shell ATF Dexron DIII, Mobil ATF 200 RED, BP Autran DX, Esso ATF Dexron, Agip ATF Dexron. This is a standard, widely available automotive transmission fluid.
What are the output speed ranges?
UDL 002: 170 to 880 rpm. UDL 005 and UDL 010: 200 to 1000 rpm. The variation ratio is approximately 1:5. All sizes work with 4-pole motors (approximately 1400 rpm at 50 Hz input).
What is the maximum output torque?
UDL 002: up to 3 Nm. UDL 005: up to 6 Nm. UDL 010: up to 12 Nm. Minimum torque (at maximum speed) is 1.5, 2–3 and 4.4–8 Nm respectively, depending on motor power.
Which motors are compatible with UDL variators?
UDL 002 — IEC 63 B5; UDL 005 — IEC 71 B5; UDL 010 — IEC 80 B5 (0.55/0.75 kW) or IEC 90 B5 (1.10 kW). All are 4-pole three-phase asynchronous motors with B5 flange mounting.