Not Shocking People
1. What is the role of A/B switch? If you are on A, would B still give you a voltage?
The A/B switch is used to change the voltage and current display to match that of what is being produced from the corresponding source. Additionally, when one (A or B) is selected, the user will be able to change the current or voltage produced from the source.
In matters of dual use, when A is currently selected and displayed, B will still be producing the same current and voltage that was selected whilst B was selected.
2. In each channel, there is a current specification (either 0.5 A or 4 A). What does that mean?
The 0.5 or 4 A specification represented over each channel, details the maximum current that may be produced by that channel.
Independent: When the independent operations is enabled, the A and B sources are separate, being able to be independently altered.
3. Your power supply has two main operation modes for A and B channels; independent and tracking. How do those operation work?
Tracking: Series: When the series tracking operation is enabled, the positive terminal of the B source is connected to the negative source of A, and vice versa, putting them in series, allowing for the user to connect leads to either the positive A terminal and negative B terminal, or the negative A terminal and the positive B terminal. This allows the user to draw more voltage.
Parallel: When the parallel tracking operation is enabled, the two sources are connected in parallel, allowing the user to draw larger currents
Fig. 1: Independent and Tracking (Power Source)
Showing how the operations of the Independent and Tracking methods work
4. Can you generate +30 V using a combination of the power supply outputs? How? (Photo)
Both voltage sources are set independently to 15 V, and are then connected in series to one another. The positive lead is connected to the positive terminal of A, and the negative lead is connected to the negative terminal of B.
Fig. 2: Result measurement of setup for +30 V
5. Can you generate -30 V using a combination of the power supply outputs? How? (Photo)
Both voltage sources are set independently to 15 V, and are then connected in series to one another. The positive lead is connected to the negative terminal of A, and the negative lead is connected to the positive terminal of B.
Fig. 3: Result measurement of setup for -30 V
6. Can you generate +10 V and -10 V at the same time using a combination of the power supply outputs? How? (Photo)
We made each source independently produce 10 volts.With both examples we connected the negative DMM lead to the ground.
Fig. 4: Result measurement of setup for -10 V
With the B channel, we connected the positive DMM lead to the positive B terminal, producing a -10 V measurement.
Fig. 5: Result measurement of setup for +10 V
With the A channel, we connected the positive DMM lead to the negative A terminal, producing a 10 V measurement.
7. Apply 5V to a 100 Ω resistor and measure the current by using the DMM. Compare the reading with the current meter reading on the power supply. At what angle of the current knob makes the LED light on? If you keep on decreasing the current limit, what happens to the voltage and current?
Fig. 6: Results of decreasing current max, working with LED
8. Where is the fuse for the power supply? What is it for?
It is on the back panel as part of the power supply cable input area. It is used to cut off power to the machine if something is wrong within the machine or if too much current is being applies to the machine.
9. Where is the fuse for the DMM? What is it for?
It is the largest of the circles on the bottom left of the input/output board. (On ours, labeled FUSED 2 A MAX) It is used to shut off the machine if something is wrong with the machine, or if there is too much current being applied to the machine.
10. What is the difference between 2W and 4W resistor measurements?
2 W and 4 W are used to represent 2 wire and 4 wire resistance measurements. The difference between the two is that with a 4 wire resistor the test lead resistance is reduced, allowing for lower resistances to be measured. The 2W can handle up to 100 ohms whilst 2W can handle 1000 ohms.
11. How would you measure current that is around 10 A using DMM?
You change the position of the input (red) lead to the 10 A input on the handheld DMM (12 on the BK PRECISION model), and change the reading/display method dial to A (not mA).