Chroma 16502 – Milliohm Meter

• Basic accuracy : 0.05%
• Pulsed test current output mode is used to reduce thermal EMFs affection on milliohm measurement
• Useful temperature conversion function for motor/ coil evaluation
• Temperature correction (TC function) regardless of material or temperature
• Standard RS-232 interface
• Optional GPIB & Handler interface

The Chroma 16502 Milliohm Meter is Chroma’s newest digital Milliohm Meter. With a basic accuracy of 0.05% the instrument offers a 0.001mΩ ~1.9999MΩ wide measurement range. It provides measurement range with 4 1/2 digits resolution. The fast measurement time is 65 ms. It suits component evaluation on production line.

The Chroma 16502 Milliohm Meter provides three kinds of mode for the different material applications. Pulsed test current output mode is used to reduce thermal EMFs affection on milliohm measurement. DC test current output mode is used to fasten measurement speed for inductive DUT. Dry-circuit test current output mode is used to measure such contact resistances where the maximum open-circuit voltage must be limited to 20mV. DC, Pulsed, and Dry-circuit test current driving modes, enable the Chroma 16502 can be properly used in DC resistance measurement for various inductive components (coil, choke, and transformer winding etc.), cable, metallic contact (connector, relay switch etc.) and conduction materials.

The Chroma 16502 provides temperature correction function. Temperature correction (TC function) without regarding to material or temperature. Users usually get different resistance value with different ambient temperature. Conventional units have the temperature correction using a copper wire at 20 ? only, but 16502 provides the converted values regardless of material or temperature.

The Chroma 16502 offers temperature conversion function. It is helpful temperature conversion function for motor / coil evaluation. Users usually should not take the motor / coil temperature through touch the surface directly when the motor just stops. The temperature conversion function shows the temperature (t) or increase in temperature (^t) of motor / coil, deriving the values from the measured resistance of the motor / coil and the ambient temperature. It is helpful for user to do the temperature evaluation of motor / coil.

The Chroma 16502 provide the menu list on front panel of LCD Display, and the programming assure that low resistance measurements can be made quick and easy. Provides a programmable Hi/Lo comparator function in absolute value or %, as well as 8 sorting bins for categorization of components.

For measurement integrity, contacting to the test device is made via a 4-terminal Kelvin connection that incorporates an automatic zeroing function to compensate for lead errors.

Standard RS232 interface, optional GPIB & Handler interface, high speed and stable measurement capabilities enable Chroma 16502 can be used for both component evaluation on the production line and milliohm measurement for bench-top applications.

FEATURES

Dry Circuit

Dry circuit test limits open-circuit voltage level to avoid any damage on contact junction while initial of contact for contact resistance measurement. The Chroma 16502 limits this open-circuit voltage level to be lower than 20mV.

R Scan

4 channels R scan with balance check function for fan motor (combined with A165017 option). Fan and motor are combined by multiple groups of coils and should be inter-balanced between coils or it may cause abnormal sound. Thus, test if the coils balance is needed. The 16502 provides R scan function plus option A165017 4 channels R scanner for customer test. For measurement more accuracy, the customer can use it with temperature compensation function. R Scan function should be coordinated with purchased option A165017 4 channels R scanner.

Compare

Selection of comparator function ON and OFF. The limit can be set to single Upper or Lower, and both, depends on the test requirement. Two setting methods are available: absolute value (upper/lower limit setting) and relative value (% of a reference value), and judgment results, indicated by Hi, PASS or Lo and beeper, are also output via Handler I/F, RS-232 and GPIB interfaces.

Bin Sorting

According to a preset range, measurements can be classified in up to ten ranks (BIN1 through BIN8, BIN0 and BIN OUT is over or lower limit). Settings are the same as for the comparator, using either absolute or relative values with results displayed and output to Handler I/F, RS-232 and GPIB interfaces.

Meas. Delay

Delay time between the test signal start output and the measurement. Generally used for DUT needs more time for charge. For some large inductance component testing, trigger delay time must be set to delay the measurement start point till test current is ready.

Average

Measurement values can be averaged to minimize display instability. The display shows the average value over a period. The number of samples to average can be set from 01 to 10.

Power Noise Filter

The measurement of micro current is easily interfered by power noise. The Chroma 16502 used advanced power noise filtering technology to filter the selected line frequency noise accordingly for accurate measurement.