Fiber Optic Isolated Voltage Probe. GE50 Gate Explorer FEATURES 50MHz bandwidth Battery powered, connects to any oscilloscope via BNC Standby feature for low power consumption ± 25V measuring range Excellent DC accuracy Increased EMI rejection High common mode rejection Low noise AutoCal/AutoTest features Internal 1kHz test generator Remote control of probe head Standard SMB input connector
APPLICATIONS Gate measuring of floating Thyristors, SiCs, MOSFETs, IGBTs, GTOs Multi-level power inverters (CHB, NPC, FC) High common mode signal measurements Cascaded topologies Medium Voltage power electronic equipment DESCRIPTION The GE50 isolated voltage probe allows the safe and accurate measurement of non-ground referenced voltages in power electronic modules or electronics. Although it is best suited for medium voltage equipment due to the isolation provided, the high common mode and EMI rejection make it a perfect choice for general low voltage measurements. The ± 25V input voltage range is ideal to measure gate voltage in various semiconductor devices and study potential problems and improvements. A calibration feature starts a routine that self-tests both units and adjusts the fiber optic link to minimize measurement errors due to temperature drifts or offsets. The calibration is carried from end to end and optionally a precision 1kHz test square wave can be injected into the input and displayed on the oscilloscope connected to the receiver. All this is done remotely from the receiver and it is not necessary to remove the input probe connector from the measured system. When not in use both emitter and receiver can be configured into standby mode, which reduces power consumption and increases battery duration. The receiver also signals the user of a possible low battery condition in both probe head or receiver. SPECIFICATIONS GE50 Specification Units Bandwidth, 3dB Maximum measurable voltage Maximum input DC-50MHz ±25 ±60 V V DC accuracy (after CAL) ±0.2 % Receiver output connector BNC
Probe head input connector Receiver output range SMB ±5 V Output ratio 0,1 V/V Receiver output impedance 50 Ω CMRR, (1MHz) 120 db Calibration time 3 s Output noise 10 mv rms Common mode voltage, max (*) ±40 kv Receiver power, normal mode 200 mw Receiver power, standby mode 10 mw Probe head power, normal mode 300 mw Probe head power, standby mode 10 mw Probe head batteries 2x1.5V AAA type Receiver batteries 2x1.5V AA type Operating temperature -0 +50 ºC Max. operating humidity, non-dondensing 85 % Fiber optic bundle length 2/8/15 m Dimensions See dimensions section Altitude max. 3000m. Indoor use only Normative references EMC IEC 61326-1:2012, ESD 61000-4-2 (A), RFI 61000-4-3 (A) Safety IEC 61010-1, 61010-2-030, RoHS 2011/65/EU * The probe head is not a handheld unit. Respect isolation distances from probe to ground
USAGE TURNING ON To turn on either the probe head or the receiver, press the TURN ON button until the ON Led lights. It takes a short press to turn on the units. If the unit fails to turn on check if the batteries are dead, and replace them. The probe head cannot be turned on remotely. TURNING OFF
The probe head can be turned off in two ways. Either directly by shortly pressing the TURN ON button or remotely by turning off the receiver while the fiber optic cables are connected to the probe head. In either case the ON led will turn off. To turn off the receiver press shortly the TURN ON button. The ON led light will turn off. As mentioned, if the fiber optic cables are connected to the probe head, it will also turn off automatically. STANDBY MODE This mode will place both the probe head and receiver (if the fiber cables are connected between them) in a low power mode for extended battery duration. It is recommended to use this feature every time the probe is not in use, even for shorts periods of time. Since the probe head can be set into low power mode remotely from the receiver, potentially dangerous situations where the measured system is floating at high voltage, are avoided. To enter standby mode, press the TURN ON button for a couple of seconds in either unit. The ON green led will start blinking. If the fiber cables are connected, the other unit will also enter low power mode. To return to normal mode press the TURN ON button shortly in either unit. If both units are connected by the fiber cables, both units will resume normal operation automatically. After normal operation is resumed the ON led will light continuously. CALIBRATION Calibration is needed to adjust the analog parameters of the fiber optic link and correct for offsets and temperature drifts in each unit. Every time the CAL button is pressed both probe
head and receiver run self-test prior to calibration. It is not necessary to remove the probe from the measured system in order to execute the calibration. Prior to calibration connect both fiber optics ensuring the correct color codes are positioned in each side. CALIBRATION SHOULD BE PERFORMED AT LEAST ONCE AFTER TURNING ON THE EQUIPMENT To execute calibration, first turn on both units and then shortly press the CAL button. The CAL led will turn on. If the cables are not connected, or for some reason both units cannot communicate, the CAL led will blink signaling an error. The calibration process will take a couple of seconds. If the procedure completed successfully the CAL led will turn off, otherwise it will blink and remain in that state. In this case, check the cable connections or the batteries in both units. FIBER OPTIC CONNECTIONS The probe head unit and the receiver are connected with 2 fiber optic cables supplied in a bundle. Both cables are differentiated by colored strip markers, yellow and red. Each connector uses a bayonet type connector that requires a small twist for it to be properly fixed in the unit.
WHEN NOT IN USE ALWAYS PROTECT THE OPTICAL CONNECTORS FROM DUST WITH THE SUPPLIED PROTECTIVE COVERS DO NOT TWIST OR BEND THE FIBER OPTIC CABLE AT SHARP ANGLES. MINIMUM BENDING RADIUS IS 6 CM Before operating the unit, connect both cables in their respective connectors following the correct color code for each side. EXTENDING THE INPUT RANGE Given the standard input SMB connector, it is straightforward to develop a voltage divider to measure voltage greater than the maximum allowed. However the greater the division factor, the more emphasis the designer should place on the frequency compensation. RECEIVER-OSCILLOSCOPE CONNECTION A BNC-BNC cable is supplied to connect the receiver to a measuring oscilloscope. Use of a good quality cable is recommended as it could affect the measurement. A 50 Ω input impedance oscilloscope or a proper termination should be used for best signal integrity. LOW BATTERY CONDITION Both the receiver and the probe head will measure the voltage of the batteries to warn the user in case of a low battery condition. The signaling threshold has been adjusted for typical alkaline AA batteries. A single red led is used at the receiver to display all 3 possible low battery cases. In case of a battery low event the BATT LOW led will quickly blink a number of times followed by a 4 second pause in the following way: -One blink: the batteries at the GE50 probe head should be replaced -Two blinks: the batteries at the GE50 receiver should be replaced
-Three blinks: the batteries at the GE50 receiver and remote probe should be replaced BATTERY REPLACEMENT The receiver uses standard 1.5V AA batteries and the probe uses 2xAAA. To replace the batteries open the back cover of the respective unit. Follow the polarity sign to replace the batteries and close the cover afterwards. REMOVE THE BATTERIES FROM INSIDE THE EQUIPMENT IF IT IS TO BE STORED DURING MORE THAN 5 MONTHS ORDERING CODES CODE GE50 Description GE50 probe system including: Head and receiver Fiber optic bundle(2m) BNC-BNC cable Batteries (2xAA, 2xAAA) Test graphs GE50FO2 GE50FO8 GE50FO15 2m fiber optic cables for GE50 8m fiber optic cables for GE50 15m fiber optic cables for GE50
DIMENSIONS