Operation - Metek Sorensen XPH Serie Operación Manual

The operation of both outputs is identical in Mode A (independent mode); the following description
applies to both. In Mode B and Mode C only Output 2 is active and Output 1 is disabled; the
description therefore only applies to Output 2, see Mode Selection section.
Setting Up the Output
With the POWER switch on (
accurately preset using the VOLTAGE and CURRENT controls; the left-hand meter shows the set
voltage and the right-hand meter shows the set maximum current.
When the
the actual voltage and the right-hand meter the actual load current.
Constant Voltage
The output voltage is adjusted using the coarse and fine VOLTAGE controls; the CURRENT
control sets the maximum current that can be supplied.
Constant Current
If the load resistance is low enough such that, at the output voltage set, a current greater than the
current limit setting would flow, the power supply will automatically move into constant current
operation. The current output is adjusted by the CURRENT control and the VOLTAGE controls
set the maximum voltage that can be generated.
The CC lamp lights to show constant current mode.
Instantaneous Current Output
The current limit control can be set to limit the continuous output current to levels down to 10mA.
However, in common with all precision bench power supplies, a capacitor is connected across the
output to maintain stability and good transient response. This capacitor charges to the output
voltage and short-circuiting of the output will produce a current pulse as the capacitor discharges
which is independent of the current limit setting.
Mode Selection
The three operating modes are selected by the front panel rotary switch situated between the
terminals.
Caution. Turn both outputs off before changing mode. Possible damage to the circuit being
powered, and to the unit itself, may occur if the mode is switched with either output still on.
Mode A: With the switch in this position the outputs operate independently and are isolated from
one another. The voltage range on each output is 0-75V and the current range 0-2A.
Mode B: With the switch in this position only Output 2 is active; the voltage range is 0-75V and
the current range is 0-4A. The controls of Output 1 are inoperative and the display is blanked.
The terminals of Output 1 are isolated from those of Output 2.
Note that with the output switch of Output 1 in the 'ON' position the Output lamp still lights but the
terminals remain open-circuit.
Note also that the range and scaling of the current limit control doubles when changing from Mode
A to Mode B, i.e. with the control set for a 1.5A limit in Mode A, the limit becomes 3A in Mode B. To
avoid possible damage to the circuit being tested the outputs should be switched off before the
mode is changed and the current limit set to the desired value before the output is switched on.
l
) and the
output switch is switched on, the ON lamp lights; the left-hand meter now shows
output off the output voltage and current limit can be

Operation

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