Digital Insulation Resistance Tester, AP-6688B Auto Range Megohmmeter 1999 Counts LCD Display 500/1000/2500/5000V Voltag
£106.16 inc. VAT (£88.47 ex. VAT)
- Tests insulation at 500V, 1000V, 2500V and 5000V for varied installations.
- Auto-ranging measurement speeds checks and reduces manual setting errors on site.
- 1999-count LCD gives clearer readings when verifying insulation resistance values.
- High-voltage megohmmeter suits troubleshooting motors, cables and industrial electrical equipment.
Why Choose OhmMeter
The Ultimate Motor Insulation Tester
When you are responsible for industrial asset reliability, standard multimeters simply do not cut it. The AP-6688B is a professional-grade digital megohmmeter engineered for UK electricians and maintenance teams who need to conduct high-voltage insulation tests on heavy-duty equipment. Whether you are checking motor windings, transformers, or long cable runs, this unit delivers the high-voltage stress testing required to identify degrading insulation before a catastrophic failure occurs.
Versatile Voltage & Massive 200GΩ Range
Unlike basic testers, this 200g ohm insulation meter gives you four selectable test voltages: 500V, 1000V, 2500V, and 5000V. This versatility means you can safely test everything from standard low-voltage distribution boards to high-voltage industrial motors. The expansive 1MΩ to 200GΩ resistance range ensures that even the slightest insulation breakdown is detected and quantified accurately.
Built for the Real-World Plant Room
We know that industrial maintenance rarely happens in perfectly lit, comfortable conditions. That is why this motor insulation tester features a large, 1999-count backlit LCD screen, making it incredibly easy to read in dark switchrooms or cramped plant areas. The auto-ranging function eliminates the need for constant dial adjustments, while the data hold feature allows you to freeze the reading on screen-perfect for situations where you need both hands to manage the test leads safely.
Technical Specifications
- Test Voltages
- 500V / 1000V / 2500V / 5000V
- Insulation Resistance Range
- 1MΩ to 200GΩ
- Display
- 1999-count LCD with Backlight
- Accuracy
- ±(5% + 5 digits)
- Safety Certification
- CE, UKCA, RoHS, CAT III 600V
- Power Supply
- 6 x 1.5V AA Batteries (Included)
- Dimensions
- 218 × 122 × 75 mm
- Weight
- 900g
Price Comparison
See how our price compares across UK retailers
| Retailer | Price | Delivery | Warranty |
|---|---|---|---|
| OhmMeter UK (Specialist)BEST | £106.16 | FREE | 12 months + UK Support |
| eBay (est.) | £132.70 | Varies | Seller dependent |
| High Street RRP | £169.86 | N/A | Varies |
Prices checked 17 July 2026. Prices may vary.
Customer Reviews
Bought this for testing heavy industrial motors at our plant. The 5000V setting is exactly what we needed, and the 200G ohm range is fantastic for the price. Easily matches the performance of our older, much more expensive testers.
Brilliant bit of kit. The backlit display is a lifesaver when you're stuck in a dingy switchroom. Delivery was spot on-arrived next day in a solid carry case.
As a motor rewind specialist, an accurate digital megohmmeter is essential. The auto-ranging on this AP-6688B saves me so much time. Highly recommend it to any UK sparks doing heavy duty work.
Very capable 5000v insulation resistance tester. Does exactly what it says on the tin. My only minor gripe is that it takes 6 AA batteries, so make sure you carry spares if you use it daily.
We use this for offshore power cable testing. It's rugged, easy to use with thick gloves on, and the data hold function is great when you're in an awkward position. Fantastic value for money.
Good solid professional megger tester alternative. The leads provided are high quality and heavily insulated. It is a bit bulky, but that's expected for a 5000V unit.
Saved our bacon last week finding an intermittent fault on a factory floor cable run. The 2500V and 5000V ranges really help pinpoint issues that lower voltage testers miss entirely.