Go Direct^® Voltage Probe (GDX-VOLT)
Specifications and User Guide

TROUBLESHOOTING

When using Go Direct Voltage to measure electric potential, check the following:

1. Are the leads properly and securely connected? The probe is designed to be used like voltmeter leads. It should be placed across a circuit element.
2. Disconnect Go Direct Voltage from any power supplies and connect via Bluetooth. Electric “noise” from a power supply, such the computer to which it is connected, can travel along the USB cable connecting it. Connecting to your device via Bluetooth removes that source of noise.
3. When measuring DC voltages with power supplies, some power supplies do not provide a steady DC signal. If the sensor voltage is fluctuating, try DC source such as a battery. If the sensor reading is correct, the problem may be the power supply.
4. Is the output appropriate? The differential input range is 20 V. Over-voltage protection is provided so that slightly higher voltages will not damage the sensor. You should NEVER use high voltages or household AC with these probes.

RELATED TIL ENTRIES

• The readings from my Current and/or Voltage Probe are erratic, but if I measure the voltage with a multimeter instead, I get a solid reading. What is wrong with my sensor?
• What is the difference between a Differential Voltage Probe (DVP-BTA) or Go Direct Voltage Probe (GDX-VOLT) and the simple Voltage Probe (VP-BTA)?
• What is the overvoltage protection on the Differential Voltage Probe and Current Probe?
• What is the accuracy of a DVP-BTA voltage probe?
• How do I measure voltages larger than 6 (or 10) volts?
• How do I measure currents larger than 0.6 amperes?
• Is it possible to use the Voltage Probe (VP-BTA) when doing an Ohm's Law experiment, or is the Differential Voltage Probe (DVP-BTA) or Go Direct Voltage Probe (GDX-VOLT) required?
• An experiment using the current sensor of the power amplifier (PAMP) gives unexpected results

SPECIFICATIONS

• Differential input voltage range: 20 V
• Maximum voltage on any input: 24 V
• Input Impedance (to ground): 10 MΩ
• Differential Impedance: >20 MΩ
• Linearity: 0.01%
• Resolution, 16-bit: 5 mV
• Supply current (typical): 9 mA
• Maximum Sampling Rate: 1,000 samples/s (USB or BLE)

CALIBRATION
Calibrate? No. The sensor is set to the stored calibration before shipping.

If you wish to calibrate the sensor, you can conduct a two-point calibration. See the user manual for details.

You may also zero the sensor before collecting data, as an alternative to calibration. This is done by shorting out the leads of the sensor, then choosing the Zero option in the data-collection software. This option adjusts the calibration offset but does not adjust the calibration gain.

BATTERY TROUBLESHOOTING
If the sensor can be turned on when connected by USB but not when disconnected from USB, it is likely that the battery just needs to be charged. In this case, charge the sensor for several hours and try again.  However, when the battery reaches its end of life and can no longer hold a charge, the sensor will behave erratically even on USB: the readings may be inaccurate, it may drop the connection, etc.  There is not a simple test to tell if this is the case, other than trying a known good battery to see if that fixes the problem.  One thing that can cause the same symptoms is also a bad USB cable, try swapping the cable with a different sensor.  In this state, the sensor cannot be used even if connected by USB, so the battery will need to be replaced. The rechargeable battery in this sensor is covered by a one year warranty but should last two to five years in typical use. Note that if the battery is less than one year old and the sensor cannot be turned on even when connected by a working USB cable, another possibility is that the USB port is bad. In this case, contact Vernier technical support for assistance. 

RELATED VERNIER PRODUCTS

• Differential Voltage Probe (DVP-BTA)
• Voltage Probe (VP-BTA)
• Instrumentation Amplifier (INA-BTA)