PS-1 Power Supply Manual




R&R Technologies, Inc.
WWW.RNRTECH.COM

R&R Technologies PS-1 Manual

Table of Contents

1.0 Introduction.

How often have you been developing a product which involves interfacing with a PC and reached the point in development where you need the product being developed next to the software/firmware development PC which is likely nowhere near the test bench?

How often have you been field testing a piece of equipment and wished you had a bench type power supply to power the unit being tested?

How often have you needed a power supply that is "truly" isolated from the power mains?

How often have you set up a "test" to run overnight, or even say for a couple of weeks and any power outage would cause the test to fail? In its normal state running from the wall transformer, the PS-1 has automatic input power fail protection.

The PS-1 features 1.2 to 15 Volts adjustable output at up to 1.00 Amps. There is an adjustable current limit/crowbar which shuts the supply off when exceeded.. This is adjustable in 10mA steps from 0.01 to 1.00 Amps. There is a single 3 digit LED display to show Output Voltage, Output Current, Input Voltage, or Current Limit setting. Charging/Operating voltage is supplied via a 24Vdc wall transformer. The PS-1 has an internal 18Vdc battery rated at 1.2AHr. The PS-1 is a switching regulator design which reduces internal heat generation. When running on batteries, the PS-1 will typically supply 5.0 Volts at 1 Amp for about 3.5 Hours. Basically, the batteries when fully charged are capable of supplying 21.6 Watt-hours of energy. The switching supply converts at about 90% efficiency at heavier loads, which gives about 19 Watt-hours of usable energy.

When you receive your PS-1 check it closely for damage...... It does have batteries inside which are quite heavy.

You should have received the following items:

The PS-1 Power Supply. A 24Vdc Wall transformer. This instruction manual.

If all looks good then go ahead and power the unit up. Briefly press the On/Off button in the upper right corner of the instrument.

You should hear a series of ascending tones and the LED display should show dashes for about 2 seconds.

Then the display will show the last voltage output setting.

Now press the select button in the upper middle of the instrument (marked Sel/Reset). Each time you press this button, it will cycle the LED display showing Output Current, Input Voltage, Current Limit setting, then Output Voltage again.

When you are displaying the Output voltage, you may adjust the output voltage with the knob in the center of the instrument. Clockwise increases it, counter-clockwise decreases it. When you are displaying Output current, or Input Voltage, the adjustment knob has no effect. When you are displaying the Current Limit setting, the adjustment knob will increase/decrease the desired current limit.

Next plug the supplied wall transformer into an appropriate wall outlet and plug the power plug into the PS-1. The power jack for the PS-1 is located in the lower right hand side of the instrument.. When you plug this transformer in, you should see the "charging" LED light up. If you are watching the Input voltage on the LED display, you will notice that it goes from about 18 Volts to about 23 Volts.

The next section will go into detail about the operations of the PS-1.

3.0 Controls and Operations.

3.1.0 On/Off switch.

This switch is used to turn the instrument on if it is off and visa versa. If the instrument is off (display is blank) then briefly pressing and releasing this switch will power the instrument up. The PS-1 goes thru a power up sequence that lasts about 2 seconds.

This switch is also used to power the instrument up in a Calibration Mode. To do this, press and hold the switch until the display shows "CAL".

3.1.1 Sel/Reset switch.

In Normal Mode this switch is used to cycle through the LED display modes. There are a series of indicator LEDs just to the left of this switch which indicate what the LED display is showing. Each press of this switch advances the display to the next item to be displayed (it cycles through Output Voltage, Output Current, Input Voltage and Current Limit setting).

3.1.2 Adjustment Knob.

In Normal Mode this knob is used to adjust the output voltage, or to set the current limit. The output voltage can only be adjusted when the LED display is showing the output voltage, likewise, the current limit can only be adjusted when the LED display is showing the current limit.

In Calibration Mode this knob adjusts the output voltage to achieve the desired calibration values (see Calibration Mode Operation).

3.1.3 Output Terminals.

The PS-1 features spring-loaded terminals for it's output terminals. These allow easier connect/disconnects, and overall are much more convenient in a test environment.  Pushing down on the spring lever allows you to insert stripped wire or a test lead into the connector.  If you are using alligator clips, you can insert a small piece of wire to clip onto, or even better, you can insert a 3/4 inch 2-46 or 4-40 screw into the connector with the head sticking out, this makes an ideal post to clip onto.  One big advantage to the spring-loaded clips is if you accidentally get caught in the leads coming from the PS-1, they rather gracefully slip out of the connector when yanked on.

3.1.4 Power Jack.

This jack is where the charging/operations power is applied to the instrument. It is located on the front panel so that the instrument can be removed from its nominal "permanent" place on the test bench without having to reach around to the back of the instrument to accomplish this. This instrument is designed to be removed from its nominal resting place on a frequent basis.

3.1.5 The Wall Transformer.

The wall transformer has been selected to be able to charge the battery and to operate the instrument to it's full capacity. So even with a fully discharged battery, the PS-1 can operate at maximum ratings (15V and 1Amp) with the wall transformer plugged in. This is very important, you may have fully discharged the battery in field use and yet need full use of the supply when you return to the test bench, alternatively (possibly more likely) you have not kept the PS-1 charging even when on the bench and you all of a sudden need it at full power.

3.1.6 The "Charging" LED.

The "charging" LED is located just above the Power Jack. It will light up when the wall transformer is plugged it and the battery is being charged. One exception: When the batteries are fully charged and have reached their "float" potential, the LED will go out.

3.2 Operations. 

3.2.0 The power-on sequence.

The PS-1 powers on through a controlled sequence to protect the instrument and the end user.  For a normal power up, press the On/Off switch briefly.

3.2.1 Normal Mode Operation.

In the normal operating state of the instrument, after the power on sequence (see above) the display shows the current Output voltage.

In normal operation, the output voltage can be adjusted with the output adjustment knob over the range of 1.2 to 15.0 Volts.

If the Sel/Reset switch is momentarily pressed, advance LED display to next measurement to display. 

• The switcher is shut off.
  
• The display shows "CL ".
• Blink the display.
• And beep the beeper.

3.2.2 Calibrate Mode Operation.

This is a special state of the instrument which allows calibration of the measurements being made. After the power on sequence (see above) the display shows "CAL".

There are two possible calibrations for the PS-1, the voltage measurements and the current measurements.

To start the calibration sequence, momentarily press the Sel/Reset switch.

First the unit will start with the voltage calibration.  If you wish to bypass the voltage calibration just momentarily press the Sel/Reset switch and unit will go to the current calibration.  Momentarily pressing the Sel/Reset switch again will go back to voltage calibration.  The calibration mode can only be exited by momentarily pressing the On/Off and turning the PS-1 off.

To calibrate the voltage measurements, you will need a voltage measuring device that is at least accurate to 0.1%.  Most 4 1/2 digit multimeters meet this standard.  Attach the multimeter or other voltage measuring instrument on the output terminals.  The voltage calibration is a two point calibration which involves setting two precise voltages.

• During calibrate the Current Limit setting is set for 1000mA. If the current limit is exceeded:
  • The switcher is shut off.
    
  • The display shows "CL ".
  • Blink the display.
  • And beep the beeper.
• This continues until the Sel/Reset switch is momentarily pressed.

4.0 Interface options.

5.0  Specifications.