OPTIONS MATRIX - Choose your instrument from the first column and follow the row across to see what options are available for your instrument. Click option links for more information about individual options.

InstrumentAmbient Temp CompIR Temp Comp Diode TestRS-232BCD FreezeSample and HoldAlarmSafety Relay 230 VACHi/Low Current Option

Temperature Compensation

Temperature changes of a few degrees in a product can produce significant changes in the resistance of the product. Temperature compensation allows for varying product temperature by providing the Model 5012-05A with the ambient temperature. The tester then compensates for differences between the ambient temperature and the standard measurement temperature. The accuracy of the temperature compensation is within 0.2% of the actual resistance between 0° and 50°C. (Back to Options Matrix)

Download Temperature Compensation Option Specification Sheet

Diode Test Option

Many of our IRT customers have the requirement to verify the presence and proper polarity of the DC shunt diode installed on a solenoid to prevent high voltage transients during coil activation and de-activation. Because the maximum test voltage produced by the Model 5012-05A is 0.200V, the shunt diode forward voltage drop is not exceeded and the diode does not conduct. This permits accurate measurement of the coil resistance up to 2000 Ohms, but does not make it possible for the resistance tester to detect the diode or its polarity.

Our newly introduced Diode Test Option effectively tests for the presence and the polarity of the shunt diode on a DC coil. The required test polarity (which terminal is the diode anode and which is the cathode) is selected by a jumper on the option board. This jumper can be front-panel mounted as necessary for production setup.

The Model 5012-05A test circuit functions in the normal manner. When the resistance test is complete, an external contact closure from the test controller or PLC is used to initiate the diode polarity test. The polarity test automatically locks the Model 5012-05A resistance reading and limit status so that it may be read while the diode test is in progress. (Back to Options Matrix)

Computer Interface

The Model 5012-05A is available with two types of computer interface, RS-232 and Binary Coded Decimal (BCD). The RS-232 interface is a three-wire link that is a standard, null-modem connection with a baud of 50 to 9600 (dip switch settable). The RS-232 interface is useful for statistical analysis of production, predictive control and data logging. It is compatible with any computer having a RS-232 port and any terminal program.

The BCD output allows the resistance tester to transmit readings to a Programmable Logic Controller (PLC). The BCD option generates a 1, 2, 4 and 8 bit for each of the 5 digits in the resistance reading. An output strobe is also provided to allow synchronization of the resistance tester with the PLC. The BCD output is a TTL logic level of 0 to 5 VDC and a maximum output current of 24mA. (Back to Options Matrix)

Freeze Option

A set of contact closures allow the operator to hold the current reading even after disconnecting from the part under test. The reading will continue to be held until the contact closure is released.

The Freeze Option is not compatible with the Diode Test Option. (Back to Options Matrix)

Sample & Hold Option

A contact closure triggers the high speed sampling of the voltage drop measured across the unknown resistance. The voltage can be acquired in as little as 10 milliseconds while the test probes are in contact with the resistance to be measured. The test voltage is stored for processing with the system analog to digital converter. The 5012-05A will display the measurement calculated from this stored voltage even though the part is no longer in contact with the test probes. The limit sensors and Go relay will operate normally. The display and limits will not update until another sample is triggered.

not compatible with the Diode Test Option. (Back to Options Matrix)

Alarm Connections

Alarm connections are available as special terminal connections for activating audible or other alarms. (Back to Options Matrix)

Safety Relays

When a resistance tester is used in a system in conjunction with high pot or surge tests, an internal safety relay can be provided to lock out the resistance tester circuitry during other testing. This will protect the test equipment from possible high voltage damage. (Back to Options Matrix)

230VAC Service

The Model 5012-05A is available with 230VAC 50Hz operation upon request at no extra charge. (Back to Options Matrix)

High or Low Current Configurations

Low or high current configurations for the Model 5012-05A are available for the various testing applications that are required for specialized procedures. High current is often required for the accurate resistance measurement of some materials. This is often true in the measurement of products having low resistance values. The option of increasing maximum current to 1 amp is available.

Typically, a very low resistance is measured by passing a very high current through a device and measuring the voltage drop across the device. However, in some applications it is necessary to measure resistance with a very low current to prevent damage to the item being tested (for example, flash bulbs, fuses, and electronically actuated explosives may be damaged by the current ordinarily required to measure their low resistance).

Optional use of a solid-state, chopper-stabilized preamplifier allows full scale, non-destructive resistance testing with only two millivolts of drop across the tested resistance. The combination of this low-current option with the four terminal resistance measuring system permits accurate measurement of very low resistance’s without risk to the product under test.

(Back to Options Matrix)

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