ABB TCC300, Руководство пользователя, Страница: 573 / 716

sensing voltage can be obtained from a common source or from independent sources
having a nominal 120 Vac output. Normally, this is line
‑
to
‑
neutral voltage, although
line
‑
to
‑
line voltage can be used if recognition is made of any phase shift between the
voltage and current signals when using line drop compensation, to avoid introducing an
unintentional grounding into the control circuitry that could result in shorting a VT
secondary. It is strongly recommended that a 1:1 ratio isolation transformer of 25 VA or
greater with required voltage accuracy be used between the control and any line-to-line PT
connections. ABB has a suitable isolation transformer available in model M-0362. Please
consult factory for availability.
Load current must be reduced by an appropriate auxiliary transformer to 0.2 A "full scale"
before connecting to the adapter panel currents. Obtain an application guide specific to
your LTC control adapter panel and follow those instructions.
In no case should the line current circuit be interrupted with the regulator
or transformer energized. Do not remove auxiliary current transformers
without shorting the current inputs. Death or severe electrical shock can
occur.
R
L
¼
B TCC300
GUID-05A26C6D-7F1A-4E76-9958-BF605FDEA8EC V1 EN
Figure 444: TCC300 and LTC Transformer Control Adapter Panel Typical
Connections
1VAC388793-MB A
Section 8
Installation
TCC300 567
User Manual