The PI-2500 is a versatile and technologically advanced primary injection test set capable of testing circuit breakers up to 2000 amperes frame size. It incorporates an improved low impedance output transformer with dual secondaries to provide optimal impedance matching to a wide range of breaker sizes. High capacity internal fan cooling allows maximum utilization of the output transformer and faster recovery after overload conditions. It is housed in a rugged aluminum frame enclosure with removable sides allowing easy access to all internal components to facilitate ease of service and maintenance. The sides are clear of protruding components, as well as locking swivel castors on one end provide ease of mobility, and allow the test set to be moved on rough surfaces. A flat area on the top surface can be used for convenient placement of manuals, breaker curve books, and auxiliary instruments. The auxiliary 120 VAC GFI protected outlet is conveniently located on the rear of the unit, and protected by a 4 ampere circuit breaker. The output stab connectors are slotted to accommodate special breaker stab adaptor plates as well as being able to connect to the optional AUX-5000 unit for increased output capacity. A series adaptor bar allows the output to be configured for 1000 amps at 15 VAC for testing breakers that require connection via cables. The test set may be plugged into any 60 Hz AC voltage source of 200-250 VAC or 400-500 VAC. The line voltage is displayed on the indicator control panel digital meter. An input selector switch can be set for 208, 240, or 480 VAC inputs. An internal voltage sensor automatically ensures that the switch is set correctly before AC control power can be turned on. The vernier adjust the output manually as well as motorized control actuated by means of a smart control switch. When the switch is pressed briefly, the vernier moves in a very small increment for fine control. When the switch is held, the vernier moves very quickly, so that the entire span may be traversed in less than five seconds. The approximate vernier position is displayed on an LED indicator bar graph. The electronically controlled tap selection uses power contactors to set the coarse tap. The unit powers up in the lowest tap position. Tap change is not allowed when output is on. The indicator/control panel features two temperature indicators: one for the output bus temperature, and the other for the overall system temperature. If either temperature exceeds a safe operating level, the interlock is asserted and the output section is de-energized. Additional thermostatic sensors in the output transformer windings will also assert the interlock if unsafe temperature levels are detected. Primary catastrophic overload protection for the test set is accomplished with input fuses having high interrupting current capacity. Overload of the output system is sensed by means of the programmed overload device on the vernier autotransformer, and thermal sensors in the transformer winding. The combination of these devices allows full utilization of the overload capability of the test set, and eliminates costly and cumbersome fuse replacement required in other test sets. The output of the test set is controlled by means of a proven SCR controller. This provides precise initial phase angle control to reduce DC offset for inductive loads and more consistent pulse currents.
The phase angle is internally adjustable, and is preset for optimal waveforms with most breakers. The measurement of output current and time is accomplished by means of the proven MAC-21, which uses highly accurate A/D circuitry and intelligent firmware to resolve true-RMS values of distorted waveforms. The entire test set has been designed for reliability, ruggedness, and ease of use. Sophisticated electronics in the indicator/ control panel and the MAC-21 provide state of the art accuracy and convenience, while simple connections allow for easy removal and replacement for transportation or service. A large bottom-mounted fan provides airflow to the transformer and output bus. The input jacks and voltage switch are protected by being mounted on a recessed rear panel.
This test set will test low-voltage, molded-case and metal-clad, direct acting AC circuit breaker from various manufactures. The test set can also be
used on high current applications like ratio transformers, and heat runs. Using SCR’s the PI-2500 eliminates closing time errors. Initiation at the zero crossover point eliminates DC offset in the current waveform and results in accurate, repeatable test results even with short-duration currents for high speed solid state or electromechanical trip devices. The reduced length and width of the test set allows it to be maneuvered in tight spaces and it can be lowered into a shaft 26” x 30”, or a manhole 40” diameter. Provisions have been made on the bottom of the frame for a lifting sling to be attached without slipping from the corners. The rugged silver plated copper stab adaptors supplied with the test set are designed to be used for both vertical and horizontal stabs, and have both ½” and ¾” output plates.
Serial port: This standard serial port may be connected to a printer, computer, or other device to print or store time and current values of test results in ASCII format. It is set for 9600 baud, 8 bits, 1 stop bit, no parity. This interface enables you to download data into various computer software programs.
Initiating Control: The advance initiate circuitry provides both pulse preset modes for cycles or seconds for output duration. The pulse mode automatically pulses the output to any preset programmed duration. This provides additional testing capabilities for electromechanical and solid state trip devices. A short preset pulse duration also allows for instantaneous tripping without preheating the breaker under test. A long preset time can used for heat runs on cables or other devices up to maximum 9999 seconds.
Zero DC Offset: Use of digitally controlled SCR’s instead of a contactor to initiate the output of the test set eliminates closing time error and thereby ensures precise initiation at the zero crossover point of the output current waveform every time. Initiation at the zero crossover point ensures symmetrical output current by eliminating DC offset in the current waveform. Therefore accurate, repeatable test results are assured even with currents of very short duration, as when conducting tests of instantaneous or short delay trips.