Surface Insulation Resistance (SIR) Test System

Surface Insulation Resistance (SIR) testing is an industry-standard way of assessing the potential of board assemblies to fail through corrosion and other processes associated with ionic contamination. These failures can be induced by material interactions, inadequate process control, or poor material performance. SIR is typically performed at elevated temperatures and humidity levels. The resistance is defined as electrical resistance between two electrical conductors. Sheet resistance, bulk conductivity, and electrolytic contaminant leakage are all factors that affect the insulation resistance.

If your product research or development requirements include surface insulation resistance testing, Thermotron's Product Test Solutions group is pleased to offer you the PTS-SIRTS-24, PTS-SIRTS-128, and PTS-SIRTS-256; our all-in-one and turn-key SIR test systems.

Designed as a single-source solution, the PTS-SIRTS offer:

1. The convenience of packaged products - all equipment and service is provided by Thermotron.

2. Peace-of-mind - all components and the finished assembly are tested for functionality before delivery.

3. The reliability you have come to expect from the Thermotron name.

These complete turn-key systems include the temperature/humidity chamber, patented test coupon holding fixture, power supply, software, and the computer-controlled testing module.

The PTS-SIRTS use a highly accurate and reliable design to measure up to 256 test coupons on standard test circuit boards. The systems use solid-state switching instead of reed relays, which eliminates leakage and enhances reliability. They are capable of measuring 1MO to 100 million MO resistance with an accuracy of better than 3% of the reading. Every input has its own individual test circuit, which allows test voltage and measurement to be applied to all test sites in parallel, significantly reducing test times. All test programming is menu driven with user-friendly prompts. The displays show test status, test values, and bias, soak, and test intervals in real time.

Key Features

• Microprocessor control for ease of use and accuracy • Choice of fully automatic or manual test cycles • No cross-channel leakage • Quick connect/disconnect • Storage of up to 12 different test procedures in nonvolatile memory, recallable at the push of a key • Two deviation alarm set points per input, programmable in scientific or decimal form • Pass/fail display lets operator read test result at a glance • Chamber environmental conditions can be reported with the test results through the control PC

The PTS-SIRTS meet and exceed the requirements for:

• ANSI/J-STD 001-006
• IPC-TM 650
• IPC-SM 840
• IPC-S-815 CL III
• MIL-F-14256D
• BELLCORE TR-NWT-000078
• ASTM D-257
• HP EL-EL861-00

They are programmable to handle any test pattern including IPC B24, B25, B36, comb, Y, and circular patterns.

System Specifications
Capacity:	8 - 24 test sites (PTS-SIRTS-24) up to 25 - 256 test sites (PTS-SIRTS-256) (other configurations are available - please ask an applications engineer for details)
Range:	1 meg ohms to 1x1014 meg ohms
Accuracy:	3% of reading
Test and Bias Voltage:	±10V, ±48V, ±100V, ±500V
Control	Current model Pentium PC with Windows XP, LCD monitor
Computer Interface:	RS-232. Sends data at every test interval in a comma-separated ASCII format.
Other:	Includes real-time clock, free software updates, 8' wiring harness
Temperature Range:	-40°C to +130°C (SM-1.0) -18°C to +110°C (SM-3.5) -68°C to +180°C (SM-5.5)
Humidity Range:	20% to 98% rh as limited by a 7°C minimum dew point & a maximum dry bulb of 88°C
Cooling Performance:	Temperature pull-down from: +25°C (+77°F) to -20°C (-4°F) in 22 minutes (SM-1.0) +25°C (+77°F) to -10°C (14°F) in 50 minutes (SM-3.5) +25°C (+77°F) to -54°C (-65°F) in 24 minutes (SM-5.5)
Heating Performance:	Temperature heat-up from: +25°C (+77°F) to +110°C (+230°F) in 19 minutes (SM-1.0) +25°C (+77°F) to +65°C (+150°F) in 15 minutes (SM-3.5) +25°C (+77°F) to +180°C (+356°F) in 30 minutes (SM-5.5)
Cubic Volume:	SM-1.0: 0.89cubic feet (25 cubic liters) SM-3.5: 3.5 cubic feet (99 cubic liters) SM-5.5: 5.5 cubic feet (155 cubic liters)
Workspace Dimensions:	SM-1.0: 14"w X 8"d X 14"h (36w X 20d X 36h cm) SM-3.5: 17"w X 18"d X 20"h (43w X 46d X 51h cm) SM-5.5: 20"w X 20"d X 24"h (51w X 51d X 61h cm)
Electrical Power:	115 volt (±5%), 1 phase, 60 cycle, 16 amps (SM-1.0, SM-3.5) 230 volt (±5%), 1 phase, 60 cycle, 25 amps (sm-5.5)
Humidity Water Usage:	1-2 gallons per hour, dependent on humidity profile.