Remote Sensing - Delta Elektronika SM 7-80 Instruction Manual

SM800
Warn ing! The 3750 Vrms can not be tested af ter wards on the
as sem bled unit be cause the in su la tion be tween the com po -
nents on the in put side to the case (like the bridge rec ti fier) is
spec i fied at 2500 Vrms. Since the in su la tion out put - case is low
(only 600 VDC) the in su la tion of the pri mary com po nents to
case will break down when 3750 Vrms is ap plied be tween in put
and out put (2500 Vrms + 600 VDC < 3750 Vrms) (see also fig. 3
- 14).
Note: when test ing the in su la tion, take care to charge and dis -
charge the ca pac i tors be tween in put - case and out put - case
slowly (e.g. in one sec ond). This to prevent high peak cur rents,
which could de stroy the power sup ply. Make sure to dis charge
the ca pac i tors com pletely be fore us ing it again.
RFI SUP PRES SION
22)
Both the in put and out put have RFI fil ters, re sult ing in very low
con ducted RFI to the line and load. Due to the out put fil ter the
out put volt age is very clean, hav ing al most no spikes.
OP ER ATING TEMPERATURE
23)
At full power the op er at ing tem per a ture range is –20 to +50 °C.
From 50 to 60 °C the out put cur rent has to be de rated lin early to
75 % at 60 °C (see fig. 3 - 15). These tem per a tures hold for nor -
mal use, i.e. the ven ti la tion open ings on the left and right side
must be free.
THER MAL PRO TEC TION
24)
A ther mal switch shuts down the out put in case of in suf fi cient
cool ing.The OT sta tus will be high. Af ter cool ing down the unit
will start work ing again.
The OT-LED on the front panel will be on and the OT-status sig -
nal will be "1" in case of a trip ped ther mal pro tec tion.
As a pre-warning the OT-LED blinks (sta tus will still be low), this
will start be fore the power sup ply shuts down.
HOLD - UP TIME
25)
The hold - up time de pends on the load and the out put volt age.
A lighter load or a lower out put volt age re sults in a lon ger hold -
up time (see fig. 3 - 16).
TURN ON DE LAY
26)
The out put volt age is avail able about 0.5 s af ter mains switch on.
IN RUSH CUR RENT
27)
The in rush cur rent is lim ited with a spe cial cir cuit.
Re peat edly switch ing on and off does not change the max i mum
peak cur rent.
Switching on and off at a fast rate can over heat the in rush cur -
rent lim iter. With the re sult that the unit does not start any more.
Af ter cool ing down (mains switched off) it will be OK again.
RE MOTE SENSING
28)
The volt age at the load can be kept con stant by re mote sens ing.
This fea ture is not rec om mended for nor mal use but only when
the load volt age is not al lowed to vary a few mil li volts. Al ways
use a shielded ca ble for sens ing.
In or der to com pen sate for the volt age drop across the load
leads, the unit will have to sup ply a higher volt age, see fig. 3 - 17:
Uout = (volt age drop across each lead) + (volt age across the load)
The volt age limit reads the volt age di rectly at the out put ter mi -
nals. The set ting for the limit must there fore be in creased by the
to tal volt age drop across the load leads.
The volt age dis play on the frontpanel and the volt age mon i tor
out put on CON E are con nected to the sense leads and there -
fore read the volt age across the load and not the volt age on the
out put ter mi nals.
The sense leads are pro tected against ac ci den tal in ter rup -
tion. The max i mum volt age be tween the out put ter mi nals and
the sense in puts is lim ited at 2.5 V.
For sens ing on a pul sat ing load see pre vi ous para graph 20).
October 2007
Hold-up time vs Vout with Iout as a parameter
Re mote sens ing, volt age drop in load leads sub -
.
DESCRIPTIONS
DELTA ELEKTRONIKA BV
fig. 3 - 15
Op er ating tem per a ture ranges
fig. 3 - 16
fig. 3 - 17
fig. 3 - 18
Mas ter / Slave se ries op er a tion
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