TECHNICAL DATASHEET

PJ Open Frame Power Supply

48V 50W 1 Phase / PJ-48V50W

All parameters are specified at 25°C ambient unless otherwise noted.

www.DeltaPSU.com (May 2013, Rev. 01)

10

Dynamic Response

Inrush Current

Inrush current is the peak, instantaneous, input current measured

and, occurs when the input voltage is first applied. For AC input

voltages, the maximum peak value of inrush current will occur

during the first half cycle of the applied AC voltage. This peak

value decreases exponentially during subsequent cycles of AC

voltage.

Overvoltage Protection

The power supply’s overvoltage circuit will be activated when its

internal feedback circuit fails. The output voltage shall not exceed

its specifications defined on Page 3 under “Protections”.

The power supply should be latch.

Short Circuit Protection

The power supply’s output OLP/OCP function also provides

protection against short circuits. When a short circuit is applied,

the output current will operate in “Hiccup mode”, as shown in the

illustration in the OLP/OCP section on this page. The power

supply will return to normal operation after the short circuit is

removed.

Overload & Overcurrent Protections

The power supply’s Overload (OLP) and Overcurrent (OCP)

Protections will be activated when output current exceeds 105%

once the power supply has reached its maximum power limit, the

protection is activated and the power supply will go into “Hiccup

mode” (Auto-Recovery). The power supply will recover once the

within the specifications.

time (depending on the load), the Over Temperature Protection

(OTP) will be activated due to high temperature on critical

components. The power supply will then go into latch mode until

the fault is removed and the mains is reapplied.

Over Temperature Protection

As

mentioned

above,

the

power

supply

also

has

Over

Temperature Protection (OTP). This is activated when the

overload condition persists for an extended duration and the

output current is below the overload trigger point but >100% load.

In the event of a higher operating condition at 100% load, the

power supply will run into OTP when the surrounding air

temperature is higher than the operating temperature. When

activated, the output voltage will go into latch mode until the

mains is reapplied and the surrounding air temperature drops to

its normal operating temperature.

The power supply output voltage will remain within ±5% of its steady state value, when subjected to a dynamic load from 0 to 50% and

50 to 100% of its rated current.

■ 0 to 50% Load

■ 50 to 100% Load