Delta Elektronika M Series User Manual

M - SERIES DELTA ELEKTRONIKA BV
Febr. 2005 Page 1 - 5
Efficiency
The 70 to 75% efficiency of the M series is high for linear
power supplies. The power supplies are dimensioned
to stay within regulation down to 198 V AC input. How
-
ever if the line voltage is already stabilized and never
drops below 215 V, the input can be connected to the
240 V tap of the transformer. This will still increase the
efficiency of the M 24-20 HE from 74 to 79%, saving
considerable heat.
Parallel operation
With parallel operation the current will not be shared
equally but the current limit of each unit will avoid over
-
loading. The current sharing is better if the load wires
are of equal length and the outputs adjusted at equal
voltages. To do this a multimeter can be used to mea
-
sure the difference of the output voltages. Remote
sensing is not recommended with parallel operation.
To enable parallel operation at higher ambient temper-
atures the current limit of all units can be set lower. At
parallel operation without separation diodes, the OVP
has to be turned out of range (high) because it is only
rated for one power supply.
Parallel operation for redundancy
For redundant parallel operation an extra positive out
-
put terminal via a built-in diode is available.
Remote sensing cannot be used.
Redundant parallel operation
Parallel operation
Output voltage adjustment range
The M-series is meant for use at a fixed output
voltage. However it can be used over a larger
range at a lower output current or with a smaller
AC input variation (see graphs). The adjustment
ranges are given below.
M 24-12 HE 24 - 28 V
M 24-20 HE 24 - 28 V
M 48-10 HE 48 - 54 V
M 15-16 HE
if connected for 12 V: 12 - 14 V
if connected for 15 V: 15 - 17 V
M 60-5HE
if connected for 48 V: 48 - 54 V
if connected for 60 V: 60 - 64 V
The M 15-16 HE has a tap on the transformer sec
-
ondary for use at 12 V instead of 15 V. To avoid
overheating of the series pass transistors it is very
important not to forget to connect it to the lower tap
when turning down the output to 12 V. The same
applies for the M 60-5 HE for 60 and 48 V.
Maximum output at
reduced
AC input voltage

Delta Elektronika M Series Specifications

General

Brand	Delta Elektronika
Model	M Series
Category	Power Supply
Language	English