DESCRIPTIONS
SM3000
Page 3 - 4
DELTA ELEKTRONIKA B.V.
rev. February 2018
14)
PRO GRAMMING BAND WIDTH
For small sig nals the band width is 50 Hz, but for large sig nals
there is a lim i ta tion in the max i mum am pli tude of the out put wave -
form. The out put ca pac i tors limit the max. slew rate. Fig ure 3 - 13
shows the max i mum peak to peak out put volt age swing as a
func tion of fre quency, with the load as a pa ram e ter. The higher
the load re sis tance the lower the max. am pli tude. The mea sure -
ments were car ried out us ing a sine wave. The DC level of the
out put is 50 % of the max. out put volt age.
15)
RE COVERY TIME
Fig ure 3 - 14 shows the re cov ery time for the SM30-100D at
25 °C, set at 30 V out put volt age, with a 50 – 100% load step.
16)
NOISE SUP PRES SION (in put / out put)
The in put / out put noise sup pres sion is mea sured with a pulse
gen er a tor (a) in se ries with the line in put or (b) be tween in put and
case (earth). The gen er a tor should pro duce a high en ergy pulse
of about 300 V. If there is an elec tri cal con nec tion be tween the
out put and the in put through the os cil lo scope, you will get a false
read ing. The sup pres sion for the SM120-25D is lower, but the
rel a tive dis tur bance on the out put is com pa ra ble to the
SM30-100D.
17)
PUL SATING LOAD
To avoid over heat ing the out put ca pac i tors, the AC com po nent
of the load cur rent should be lim ited (see fig. 3 - 15).
One method of de creas ing the AC cur rent through the out put ca -
pac i tor is by us ing a large ex ter nal elec tro lytic ca pac i tor in par al -
lel with the load. Care must be taken so that the ca pac i tor in
com bi na tion with the lead in duc tance will not form a se ries res o -
nant cir cuit!
When us ing
re mote sens ing
on a pul sat ing load (for in stance a
DC-mo tor), use a ca pac i tor in se ries with a re sis tor over the load
(see fig. 3 - 16). Like this the AC-com po nent caused by the pul -
sat ing of the load is fil tered.
With pul sat ing loads the
I-monitor out put
should not be used.
fig. 3 - 13
Max. peak to peak out put volt age swing vs fre quency
fig. 3 - 14
Re cov ery time SM30-100D
50 - 100 % load step, Vo=30 V
fig. 3 - 15
Pul sating load current
