Tom, Bret et al;
I agree with you ........... something is not right. I see my K3S
draws about 1.2 amps DC on receive. at 1.38 volts that's about 17
watts. If my supply is only 50% efficient, that's 35 watts. I can't
understand where the 350 watts would be used unless other equipment is
being used. And I agree that transmit is 20 amps at 13.8 volts or 276
watts. Again with a supply that is 50% efficient, that is only 550
watts or so. Certainly no where near the "over 900 W".
Perhaps the computer, monitor, lamp, printer and other ancillary
equipment is part of the load on the UPS. It is more likely the
inductive load on the UPS is creating an issue with the power output
indication. Although that doesn't explain the UPS shut down or fold
back in power. One other issue regarding the UPS, is the output Pure
Sine Wave, Modified Sine Wave or Square Wave? This may have a
significant impact on its function with various types of loads.
One way to evaluate the indication of the UPS output is to use an
incandescent bulb of 150 to 300 watts. They are resistive and
reasonably accurate with regard to power consumption. Don't use any of
the bulbs which are "equivalent" rated ones. I use this method as a
load when I've had to repair any of my DC to AC inverters.
73
Bob, K4TAX
On 8/30/2017 6:50 AM, KQ5S-Tom wrote:
Something is not right. If your UPS is showing 350 with the K3S at idle and
over 900 on transmit that is a difference of close to 600. The K3S draws 17-22
amps at full key down and 100 watts. Assume 20 amps at 13.8V. That is only
276. You are showing double that.
---------
KQ5S-Tom
On Aug 30, 2017, at 6:16 AM, MaverickNH <cbjesse...@comcast.net> wrote:
As mentioned in another thread, I'm running my shack on a UPS that is rated
1500va/900w. With my K3S/100 and other hardware plugged in on the same input
the UPS often max's out at 900W at < 100W on the K3S. Typically, the
baseline with K3S on RX is ~350W and it spikes over 900W with TX at 100W and
the UPS limits output. So it seems 100W isn't 100W.
I'm looking to switch in another UPS rated 2200VA/1320W, or 420W higher, for
use with the KPA500/KAT500 I just acquired from another forum member. so
from a 100W station to a 500W station. Might this work or is the increase in
watt TX not equal to the watt drawn?
BRET/N4SRN
--
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