RWB II ROTARY SCREW COMPRESSOR UNITS
INSTALLATION
S70-200 IOM
Page 15
Motor starter and interlock wiring require ments are shown
in the Starter Wir ing Diagram. All of the equipment shown
is sup plied by the installer unless a starter package is pur-
chased separately from Frick. Starter packages should
con sist of:
1. The compressor motor starter of the specifi ed HP and
voltage for the starting method spec i fi ed (across-the-line,
au totrans form er, wye-delta, or solid-state).
NOTE: If starting methods other than across-the-line
are de sired, a motor/compressor torque anal y sis must
be done to ensure that suffi cient starting torque is avail-
able, par tic u lar ly in booster applica tions. Contact FRICK
if as sis tance is required.
2. If specifi ed, the starter package can be supplied as a
com bi na tion starter with circuit break er disconnect. Howev er,
the motor overcurrent protection/disconnection device can
be ap plied by oth ers, usually as a part of an elec tri cal power
dis tri bu tion board.
3. The oil pump starter with fuses, or in the case where the
com pres sor motor is a different volt age from the oil pump
motor, with a circuit breaker disconnect suitable for sepa rate
power feed.
4. A 2.0 KVA control power trans form er (CPT) to supply 120
volt con trol power to the mi cro pro ces sor con trol system and
sep a ra tor oil heaters is included. If environ mental condi tions
re quire more than the usu al two 500 watt oil heat ers, an ap-
pro pri ate ly over sized con trol trans form er will be re quired. If
fre quent power fl uc tuations are anticipat ed or ex treme ly noisy
power lines are encoun tered, a reg u lat ing control trans form er
should be con sid ered. Contact FRICK for as sis tance.
5. For customer-supplied across-the-line starters, a shunt-
ing device must be installed across the Current Trans form er
(terminals 3 & 4).
If the shunting device is not in-
stalled, the Analog I/O board on
the Quantum panel may be severly
dam aged at start-up (see Starter Wiring Diagram,
Fig ure 15).
6. One each normally open compressor motor and oil pump
motor starter auxiliary contact should be supplied. In ad di tion
to the com pres sor and oil pump motor starter coils, the CT
and CPT sec ond ar ies should be wired as shown on the start-
er pack age wiring diagram. The load on the control pan el for
the compressor motor starter coil should not ex ceed a Nema
size 3 starter. For larger starters, an in ter pos ing re lay must
be used to switch the compres sor motor starter coil(s).
NOTE: Do not install a compressor HAND/OFF/AUTO
switch in the starter package as this would bypass the
compressor safety devices.
7. The compressor motor Cur rent Trans form er (CT) is in-
stalled on any one phase of the com pres sor leads.
NOTE: The CT must see all the cur rent of any one phase,
there fore in wye-delta ap pli ca tions BOTH leads of any
one phase must pass through the CT.
CURRENT TRANSFORMER (CT) RATIOS
The CT ratio for various motor sizes (with a 5 amp second-
ary) is given in the following table:
VOLTAGE
HP
200
230
380
460
575
2300 4160
20 100:5
100:5 50:5 50:5 50:5 -
-
25 100:5
100:5 50:5 50:5 50:5 -
-
30 200:5 100:5 100:5 50:5 50:5
-
-
40 200:5 200:5 100:5 100:5 50:5
-
-
50 200:5 200:5 100:5 100:5 100:5
-
-
60 300:5 200:5 200:5 100:5 100:5
-
-
75 300:5 300:5 200:5 200:5 100:5
-
-
100 400:5 300:5 200:5 200:5 200:5
-
-
125 500:5 400:5 300:5 200:5 200:5
-
-
150 600:5 500:5 300:5 300:5 200:5
-
-
200 800:5 600:5 400:5 300:5 300:5 100:5 50:5
250 800:5 800:5 500:5 400:5 300:5 100:5 50:5
300 1000:5
1000:5 600:5 500:5 400:5 100:5 50:5
350
- 1000:5 800:5 500:5 500:5 100:5 100:5
400
-
-
800:5 600:5 500:5 200:5 100:5
450
-
- 1000:5 800:5 600:5 200:5 100:5
500
-
- 1000:5 800:5 600:5 200:5 100:5
600
-
- 1200:5
1000:5 800:5 200:5 100:5
700
-
-
- 1200:5
1000:5 200:5 200:5
800
- - - -
1000:5
300:5
200:5
900
- - - -
1200:5
300:5
200:5
1000
- - - - -
300:5
200:5
1250
- - - - -
400:5
200:5
1500
- - - - -
500:5
300:5
MINI MUM BURDEN RATINGS
The following table gives the minimum CT burden ratings.
This is a function of the distance between the motor starting
package and the compressor unit.
BURDEN
MAXIMUM DISTANCE FROM
RATING FRICK
PANEL
USING #
USING #
USING #
ANSI
VA
14 AWG
12 AWG
10 AWG
B-0.1
2.5
15 ft
25 ft
40 ft
B-0.2
5
35 ft
55 ft
88 ft
B-0.5
12.5
93 ft
148 ft
236 ft
