High Voltage Level 2 Training

Commandment 7

Always review the test setup with the subject-matter expert (SME) prior to enabling the high voltage test for the first time

Commandment 11

Always submit a test request to test lab coordinator

State the minimum HV DC electrical current flow through the human body that is considered lethal.

Anything greater than 5 mA is considered lethal.

Commandment 9

Ask yourself: "Is the test circuit isolated correctly?"

List at least 7 basic testing devices used in your HV lab: (a) provide hypothetical examples in which you would use the equipment, and (b) cautions on what could go wrong if used improperly.

CAN Box: Used to measure the CAN signals, if not set up correctly could provide a false sense of security.

List at least 7 basic testing devices used in your HV lab: (a) provide hypothetical examples in which you would use the equipment, and (b) cautions on what could go wrong if used improperly.

Clamp on current reader: Another device used to measure current without interrupting the system, if used improperly can proved incorrectly measurements

List at least 7 basic testing devices used in your HV lab: (a) provide hypothetical examples in which you would use the equipment, and (b) cautions on what could go wrong if used improperly.

DMM: Used to read the voltage of a system, if used improperly can expose the user to HV

6 step method

Dance Every Great Idea So Vigorously!

List at least 7 basic testing devices used in your HV lab: (a) provide hypothetical examples in which you would use the equipment, and (b) cautions on what could go wrong if used improperly.

Decade Box: used to create multiple values of resistance to test HV safety systems, if used improperly can wrong give wrong value and accidently overload the system.

Commandment 5

Don't defeat any safety feature, either on the DUT or on the test equipment

Step 1

Familiarize yourself with the DUT

What failure is "is the DUT isolated" trying to prevent?

If the Device Under Test is Isolated, we can prevent the following failures, -To block the transfer of high or hazardous voltages -To break ground loops -Dangerous voltages from passing to the operator in the event of an electrical fault/failure or during a surge from lightning. -They are also important in preventing fire hazards, breaking ground loops, and eliminating transient noise in electrical systems.

How would you electrically isolate a thermocouple from a high voltage device? Can scotch tape be used? How do you know yes or no?

In isolating a thermocouple, you need to place an insulating tape on the surface and to the hole of the thermocouple. Scotch tape would not be sufficient due to the high temp melting the tape and causing failure. use a high voltage rated material, such as Mylar tape, to isolate the thermal couple.

When working with HV at your facility, you, as well as the person you are working with (you never work alone on HV), are unsure about the measurement value; something seems to be out of the ordinary. What should you do?

In the lecture, when his meter was not working, he stopped his testing and reviewed with the person he is working, what they did right and what they did wrong. They swapped the DMM they were using and redid the reading, and they got the correct meeting.

When is it acceptable to use your high voltage rubber gloves without the outer leather shells (specify the voltage and current limits)? Explain the process used to verify the integrity of the rubber gloves and the frequency of this method.

It is acceptable to use your high voltage rubber gloves without the outer leather shells when using class 0 gloves, or a limit of 50V. The process to verify the integrity of the gloves includes blowing air into the glove and rolling it up for a few seconds to ensure there are no holes.

What are the possible outcomes of a poorly crimped or un-torqued HV joint?

Main concerns would be with HV, it would create higher heat leading to component damage and potential fire hazards

Commandment 8

Make sure the device under test (DUT) and all test equipment are on the same ground

Step 6

Measure High Voltage

State the internal impedance of a typical DMM and why this is important.

Multimeters use high impedance, which means that they do not draw much current from the circuit Being measured. This is important because it means that the multimeter will not affect the circuit measured.is is important because the DMM will give a false reading if the impedance is too low, drawing a large current.

Commandment 4

Never work alone

You have just completed the setup of a test that involves HV. What are the next steps you need to take prior to running the test?

One the setup is completed I will proceed with the 6-step method on running my test, familiarizing myself with the test I need to do, make sure the equipment I am using I am using is up to code, make sure the DUT ground is secure, no isolation faults, verify the easily accessible sub-components and confirm the HV is on.

List at least 7 basic testing devices used in your HV lab: (a) provide hypothetical examples in which you would use the equipment, and (b) cautions on what could go wrong if used improperly.

Oscilloscope w/ HV probes: used to measure noise/ communication over HV, if used improperly for example not using the HV probes can damage the equipment.

When measuring high voltage with an oscilloscope, what device is used to protect the scope?

Oscilloscopes are HV passive probes that allow it to be in contact with HV devices and not potentially damage the oscilloscope.

List at least 7 basic testing devices used in your HV lab: (a) provide hypothetical examples in which you would use the equipment, and (b) cautions on what could go wrong if used improperly.

Regenerative power supply: Used for battery simulators, if used correctly could shock the tester

Commandment 3

Remove the services disconnect and/or open the high voltage circuit to be reviewed

Commandment 1

Trust no one

Commandment 2

Use personal protective equipment's (PPE) if required

Step 4

Verify Isolation

Step 5

Verify easily accessible sub-components

Commandment 6

Verify equipment operation prior to performing any testing

Step 3

Verify the ground

Commandment 10

Verify the testing sampling rate and ask yourself: "will I get the data that I need to see the event?

Step 2

Verify your test equipment

List at least 7 basic testing devices used in your HV lab: (a) provide hypothetical examples in which you would use the equipment, and (b) cautions on what could go wrong if used improperly.

Voltage Detectors. Voltage detectors are used to check for the presence of live voltage on AC circuits, switches, and outlets. If used improperly, this device can shock the user. Borescope. Used to inspect the condition of industrial systems and equipment. If used improperly, one could cause a voltage spike in this device.

When measuring current in a circuit, which device is safer to use; a clamp on a meter or a Digital Multimeter (DMM)? Explain why.

When working with a DMM you are creating a circuit and when those ends are exposed it is creating potential ends that can lead to risk, but with a clamp you are not opening a circuit and can safely take your measurement.

Select safety features in HV Lab are as follows:

1. First Aid 2. Fire Extinguisher 3. Fire Alarm 4. Safety Hook 5. Knox Box 6. AED Automatic External Defibulator

Can a fuse or resistor be used to protect you when working with a HV electrical Circuit?

1. Fuse main goal is to protect the electrical components by minimizing the amount of current 2. Resistor main goal is to regulate the current