Chauvin Arnoux CA 6550 10 kV Insulation Tester

CA 6550 is a high-end portable megohmmeter from Chauvin Arnoux that tests insulation at up to 10,000 V DC and resolves resistance up to 25 TΩ, with diagnostic tests such as DAR, PI and DD, voltage ramp and step tests, and a graphic display that plots resistance, voltage and current against time.

A 10 kV insulation diagnostic instrument for cables, motors and transformers

The manual describes the CA 6550 and CA 6555 as high-end portable instruments for very high insulation and resistance values, in a rugged site housing with a cover, running from battery or mains. The CA 6550 tests up to 10,000 V; the CA 6555, covered by the same manual, goes up to 15,000 V. Both are controlled by microprocessors that acquire, process, display and store the measurements.

Beyond a single reading it runs fixed-voltage, adjustable, ramp, ten-plateau step, early-break and current-limit tests, calculates the DAR, PI and DD ratios, measures capacitance and residual current, and discharges the tested item automatically at the end.

Functions listed in the manual

• Fixed test voltages of 500, 1,000, 2,500, 5,000 and 10,000 V DC, or an adjustable voltage from 40 V in 10 V steps up to 1,000 V and then in 100 V steps.
• Ramp tests (presets 50 to 500 V, 500 to 5,000 V, 1,000 to 10,000 V) and stepped tests with ten plateaus of equal duration.
• Early-break and break-at-current-limit tests, with programmable maximum output current of 0.2 to 5 mA.
• DAR, PI and DD ratios, capacitance measurement and temperature-referred resistance.
• Plots of R(t), U(t), I(t) and I(U) on a 320 x 240 pixel graphic screen, with optional sample storage.
• Memory by object and test, USB interface and MEG software for export.
• Audible alarm thresholds, timer and digital filtering of readings.

Technical specification

Insulation resistance

Other measurements

General specification

CA 6550 or CA 6555

The two instruments share the same manual and functions; the difference stated in it is the maximum test voltage, 10 kV for the CA 6550 and 15 kV for the CA 6555, with the 15,000 V fixed point and the upper resistance range belonging to the CA 6555. Confirm the voltage and resistance ranges you need against the manual before ordering.

Test procedure and safety notes

Disconnect the item under test from the mains first. For low insulation values connect the red lead between earth and the + terminal and the blue lead to the conductor; for very high values the guard lead with its jack plug reduces surface leakage. The manual warns that humidity strongly affects insulation, so do not test when the temperature is below the dew point.

A step test stresses the insulation and can cause a breakdown, unlike the ramp test; the manual treats a drop of 25 % or more in resistance between plateaus as a sign of deterioration and recommends early-break or current-limit stop to protect the item.

Use in Oman and the GCC

Power utilities, oil and gas plants, desalination stations and industrial sites that maintain medium-voltage cables, large motors, generators and transformers use polarisation index and DAR tests to trend insulation over time. High ambient temperature and humidity along the coast raise leakage, so recording temperature and humidity with each test and referring results to a reference temperature, as the instrument allows, keeps readings comparable between shutdowns.

Accessories and spares

Delivery includes a 2 m mains cord, an optical-USB cable, two 3 m high-voltage safety cables (red and blue), a 3 m guarded black cable, a 0.5 m guarded blue cable, an accessory bag and a USB drive with the manuals and MEG software. Optional 8 m and 15 m cables and the C.A 861 and C.A 846 thermometers are listed. See the Portable Test & Measurement category for related instruments.

Frequently asked questions

What is the maximum test voltage of the CA 6550?

10,000 V DC. The CA 6555 covered by the same manual extends this to 15,000 V.

Which diagnostic ratios does it calculate?

DAR (dielectric absorption ratio), PI (polarisation index) and DD (dielectric discharge index), plus capacitance and temperature-referred resistance.

How long does charging take?

Between 6 and 10 hours depending on the initial charge. Use during charging is possible, but charging stops when the test draws close to 10 W.

What ingress protection does the case have?

IP 65 with the housing closed and IP 54 with it open, plus IK 04 impact rating.

Is Seven Star LLC a Chauvin Arnoux distributor?

No. Seven Star LLC is an independent supplier in Muscat that sources Chauvin Arnoux products on request.

Documents and quotation

Download the official Chauvin Arnoux user manual for CA 6550 from this page. As an independent supplier based in Muscat, Seven Star LLC supplies Chauvin Arnoux items on request: use the quote form with the quantity you need. Check every value in the document against your own specification before you order. Browse similar items in the category.