e) Then, to lock up the control panel, press
enter,
or wait three minutes for the
automatic time-out.
5.5.1 Verifying rms line voltage in offline mode
a)
From the offline menu, Select AC, and press enter. The display shows
rms voltage for
L2
, eg
220.
b)
To exit, press enter. The display returns to the
AC
menu header.
5.5.2 Setting the output voltage range in offline mode
a)
From the offline menu, Select
CAL
, and press
enter
. The display
shows the present rms voltage set for 100% dimmer output, eg
220
.
b)
Use the
▲
and
▼
keys to change the rms voltage output scale, in
steps of one volt.
c)
Press
enter
to save the new value and exit to the offline menu.
This function has a very useful by-product: for example, in a TV studio
where the dimmers are being fed from their own transformer, it may make
sense to specify, say, a 240V supply, where 220V lamps are to be used
in the studio. Given that a loss in the region of 4V rms can be expected at
the dimmer (dependent on choke type), plus an average cable loss – say
3V rms (dependent on installation), the highest voltage that can be deliv-
ered to the lamp will be around 233V. But by setting the Smartrack refer-
ence voltage to 227V, the dimmers will regulate to provide a constant
220V at the lamp, even though supply voltage may fluctuate at any level
above 227V.
This means that, unlike many digital dimmers, Smartrack is able in these
circumstances to regulate accurately over the full dimming range, not just
at levels below 100%.
page 34
Smartrack User Manual
ETC Ltd