Introduction
The XPH 35-4D and XPH 35-4Tv provide high levels of power (up to 305 watts) in a compact and
attractive case style.
High resolution controls allow precise setting of voltage and current levels which are indicated on
accurate and legible digital meters.
Excellent line and load regulation are matched by low noise and good transient response. High
power efficiency ensures that the unit remains cool without any fan noise.
The XPH 35-4D has two independent and isolated outputs each with a 0 to 35V, 0 to 4A
capability. The outputs operate in constant voltage or constant current mode with automatic cross-
over and mode indication. Each output has its own on-off switch. Where higher voltages or
currents are required the outputs can be wired in either series or parallel to provide voltages up to
70 volts or currents up to 8 Amps.
The XPH 35-4T has, in addition, an Auxiliary ‘logic voltage’ output with a 5A current capability. To
reflect the increasing usage of low-voltage logic devices, this output can be preset between
1.5 volts and 5 volts via a front panel control.
The total power capability is 280 watts for the dual supply and 305 watts for the triple.
The XPH series incorporates separate digital voltage and current meters on each main output.
The meters use bright 14mm (0·56”) LED displays and have an update rate of 4 per second
providing near instantaneous response. Simultaneous metering of voltage and current provides
accurate information “at a glance” and avoids any possibility of misinterpretation. When an output
switch is set to “off”, the current limit setting is displayed enabling conditions to be set before the
load is connected. With the right-hand main output off, the right-hand meters can be used to
momentarily display the preset Auxiliary voltage and current limit.
The XPH series has been designed to meet the stringent requirements of relevant IEC standards
for safety and EMC, including harmonics emissions. All outputs are intrinsically short circuit proof,
and are protected against external voltages and reverse currents.
Specification
MAIN OUTPUTS
Voltage Range:
0V to 35V minimum.
Current Range:
0A to 4A minimum.
Output Voltage Setting:
By coarse and fine controls.
Output Current Setting:
By single logarithmic control.
Operating Mode:
Constant voltage or constant current with automatic cross-over.
Output Switch:
Electronic. Preset voltage and current displayed when off.
Output Terminals:
Universal 4mm safety binding posts on 19mm (0·75”) pitch.
Output Impedance:
Typically <5m
Ω
in constant voltage mode.
Typically >50k
Ω
in constant current mode.
Output Protection:
Output will withstand up to 40V forward voltage.
Reverse protection by diode clamp for reverse currents up to 3A.
Load Regulation:
<0·01% of maximum output for 90% load change.
Line Regulation:
<0·01% of maximum output for 10% line change.
Ripple & Noise
(20MHz bandwidth):
Typically <2mVrms, <10mVpk-pk (CV mode).
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