ULVAC HELIOT 901W1 — Helium and Hydrogen Leak Detector
The HELIOT 901W1 is the oil rotary vane pump base-type model in the ULVAC HELIOT 900 series. It is designed for fixed test stations and bench-mounted applications where a compact footprint and low power consumption are important. The 901W1 uses an oil rotary vane backing pump with the smallest pump capacity in the 900 series (30/36 L/min at 50/60 Hz), making it appropriate for test objects with moderate internal volumes.
Configuration Summary
- Form factor: Base type (desktop/bench mount), low-height cart available as option
- Backing pump: Oil rotary vane pump
- Backing pump capacity: 30 L/min at 50 Hz / 36 L/min at 60 Hz (1.8/2.2 m³/h)
- Integrated oil mist trap: Yes (built-in to 901W1; oil mist trap element is a consumable)
- Inlet port: NW25 (ISO)
Technical Specifications
Values confirmed from ULVAC catalog 1855E-7 / 2018101000SP unless marked [REQUIRES VERIFICATION].
| Parameter | Value | Notes |
|---|---|---|
| Model | HELIOT 901W1 | From ULVAC catalog; verify against nameplate |
| Detectable gas | ⁴He (helium), H₂ (hydrogen) | Vacuum method only |
| Min. detectable leak rate (⁴He) | <5×10⁻¹³ Pa·m³/s | ULTRA flow mode |
| Min. detectable leak rate (⁴He) | <5×10⁻¹² mbar·L/s | ULTRA flow mode |
| Leak rate display — ULTRA | 1×10⁻¹⁴ to 1×10⁻⁶ Pa·m³/s | — |
| Leak rate display — FINE | 1×10⁻¹² to 1×10⁻⁵ Pa·m³/s | — |
| Leak rate display — GROSS | 1×10⁻¹° to 1×10⁻³ Pa·m³/s | — |
| Inlet pumping speed (⁴He) — ULTRA | 5 L/s | TV1 port open |
| Inlet pumping speed (⁴He) — FINE | 1 L/s | TV2 port open |
| Max. inlet pressure — ULTRA | <2 Pa (<0.02 mbar) | Test object must be below this before ULTRA mode |
| Max. inlet pressure — FINE | <100 Pa (<1 mbar) | — |
| Max. inlet pressure — GROSS | <1,200 Pa (<12 mbar) | — |
| Main TMP | 31 L/s | Turbomolecular pump |
| Backing pump type | Oil rotary vane | — |
| Backing pump capacity | 30/36 L/min (50/60 Hz) = 1.8/2.2 m³/h | From catalog spec table |
| Body weight | ~33 kg | Without cart |
| Weight with optional cart | ~46 kg | With low-height or standard floor cart |
| Power consumption | 600 VA | — |
| Input power | 100–120 V or 200–240 V AC | — |
| Inlet port | NW25 (ISO) | — |
| Startup time | <2 min | — |
| Interfaces | RS-232C, RS-485, analogue DC, digital I/O | — |
| Controller | 7″ tablet, wireless IEEE 802.11 b/g/n | Standard accessory |
| Wireless range | 40 m | Typical; may vary by environment |
| Wired cable | 2 m standard, 5 m optional | — |
| Battery life | 3–5 hr | Typical; varies by settings and usage |
| Languages | English, Japanese, Korean, Chinese (S/T), German, Spanish, Russian | — |
| Standards | CE, IP30 | — |
| Operating temperature | 10–40°C, non-condensing | — |
| Dimensions W×D×H (body) | 320×480×505.5 mm | With low-height cart: 320×652×917 mm |
Test Methods Supported
Vacuum (Evacuation) Method
The test object is evacuated and connected to the NW25 inlet. Helium is applied to the outside. Three sub-modes allow selection by test object pressure and required sensitivity:
- ULTRA flow: <2 Pa inlet, 5 L/s, highest sensitivity
- FINE flow: <100 Pa inlet, 1 L/s
- GROSS flow: <1,200 Pa inlet, fastest mode for large-leak screening
Sniffer Method
Compatible with optional sniffer units AS9, BS9, and BT9. The test object is pressurised with helium and the probe is scanned externally. Sniffer mode leak rate display range: 1×10⁻¹° to 1×10⁻⁵ Pa·m³/s.
Applications
- Fixed bench-mounted leak test stations in production lines
- Piping assemblies and vacuum components
- Automotive parts, air conditioning components
- Pharmaceutical and food packaging (hermetic integrity)
- Heat exchanger testing
- Scientific vacuum equipment
- Helium and hydrogen flow/permeation rate measurement
When to Select 901W1 Over Other 900 Series Models
| Requirement | Recommendation |
|---|---|
| Fixed station, small test object volume, oil pump acceptable | ✓ 901W1 is suitable |
| No pump oil allowed (clean room, pharma, food) | Use 901D2 (dry pump) instead |
| Need to move instrument between stations | Use 904 series cart model instead |
| Large test volume needing fast pump-down | Use 904W2 or 904D4 (larger pump) |
Service — What Can Be Inspected and Maintained
The following service work can be carried out on the HELIOT 901W1 by a qualified service engineer:
Inspection and Verification
- Visual inspection — leaks, damage, corrosion, cable condition
- Pirani gauge reading verification
- Pump-down time measurement against baseline
- Inlet blank-off pressure test
- TMP speed and temperature check
- Internal calibrated leak verification
- External reference leak calibration check
- Sensitivity stability measurement
- Response time and recovery time measurement
- Helium background level assessment
Maintenance and Repair
- Ion source (IS-BA1) inspection and cartridge replacement
- Oil mist trap element replacement (901W1 integrated trap)
- Rotary pump oil level check and oil change
- Rotary pump gas ballast check
- Cooling fan filter cleaning or replacement (panel and electrical)
- Vent line filter replacement
- O-ring inspection on inlet flange and internal connections
- Calibrated leak condition check
- RS-232C / RS-485 / EXT.I/O signal verification
- Tablet controller battery and software configuration check
- Backing pump ultimate pressure measurement
Consumable Parts
| Part | Service interval |
|---|---|
| Ion source (IS-BA1) | When sensitivity drops or emission is unstable; verify internal calibration first |
| Oil mist trap element (901W1) | Inspect periodically; replace when saturated |
| Rotary pump oil | Per pump manufacturer schedule; oil condition inspection at maintenance |
| Pirani gauge head | Replace when readings are consistently incorrect |
| Micro separator | Inspect at maintenance; replace if contaminated |
| Panel cooling fan filter | Inspect at maintenance; clean or replace |
| Electrical system cooling fan filter | Inspect at maintenance; clean or replace |
| Vent line filter | Inspect at maintenance; replace if contaminated |
Note: Maintenance intervals depend on operating conditions, pump-down frequency, helium exposure, and ambient environment. No fixed calendar intervals are published in the catalog. Interval determination requires review of actual operating hours and conditions.
Related Models
HELIOT 901D2 — same base form factor, dry scroll pump (no oil, larger pump capacity)
HELIOT 904W2 — mobile cart, larger oil rotary pump
HELIOT 900 Series overview and comparison
Request Service
Email: mail@ulvacheliot.com
Please include: model (HELIOT 901W1), serial number from nameplate, fault description or service required, operating hours if known, and facility country/location. We will respond within 1–2 business days.
Repair | Preventive Maintenance | Calibration | Spare Parts | Training
Regional Variants and Part Numbers
The HELIOT 901W1 is available in regional variants with different power supply configurations and certifications. Specify the complete model designation including suffix when ordering replacement parts or accessories.
| Model designation | Part number | Supply voltage | Certification | Region |
|---|---|---|---|---|
| HELIOT 901W1-F1A | 210006829400 | AC 100–120 V | PSE / UL / CSA | US / North America |
| HELIOT 901W1-F2B | 210006829900 | AC 200–240 V | PSE / UL / CSA | US / Taiwan |
| HELIOT 901W1-F2E | 210006830900 | AC 200–240 V | IEC | EU / international |
| HELIOT 901W1-F1Z | 210006875400 | AC 100–120 V | — | Without power supply cable |
| HELIOT 901W1-F2Z | 210006875900 | AC 200–240 V | — | Without power supply cable |
Panel-mount variant (HELIOT 901W1-P) is available with suffix designations J1A-P through F2Z-P. Requires PLC unit PFXGP4115T2D (210006935000) and PLC cable. Contact us for panel-mount specifications.