ONICON Incorporated 727-447-6140
Page 15
www.onicon.com
SYSTEM-20 BTU METER
The System-20 is provided with three ¾" conduit openings along the bottom
of the enclosure for power and signal cables. Two openings are provided with
knockout seals. The power cable should enter the enclosure through the right
hand opening. Do not remove the seals from unused openings. To access the
wiring connections, remove the two cover screws shown below.
3.3 ELECTRICAL INSTALLATION
AC/DC POWER IN
1
2
3
4
5
6
AUX POWER OUT
(A)
(A)
(B)
(B)
(A)
(A)
(B)
(B)
2 4
WIRE
1
TB5 TEMPERATURE
2
3
4
5
RS485+
RS485-
RS485COM
SHIELD
IN 1 (+)
IN 1 (-)
IN 2 (+)
IN 2 (-)
IN 3 (+)
IN 3 (-)
OUT 1 (+)
OUT 1 (-)
4-20mA OUT (+)
4-20mA COM (-)
0-10V OUT (+)
0-10V COM (-)
1
TB1 RS-485
2
3
4
1
2
3
4
5
1
2
3
4
5
1
2
3
4
1
2
3
4
1
2
3
4
1
2
3
1
2
3
4
5
TB6 RTD SUP
TB7 RTD RET
TB8 TURB TB9 FLOWMETER
TB2 PULSE IN
6
6
TB 3 PULSE OUT
TB4 ANA OUT
SUPTEMP (+)
SUPTEMP (-)
SHIELD
RETTEMP (+)
RETTEMP (-)
24VTURB
OUT 2 (+)
OUT 2 (-)
OUT 3 (+)
OUT 3 (-)
TURB FREQ
TURBCOM
24 VDC (+)
4-20mA IN
FREQ IN
SIG COMM
24 VDC (-)
EARTH
24V N (-)
24V L (+)
EARTH
24V N (-)
24V L (+)
24V ONLY
!
JMP1
RS485 LOAD
TERMINATED
UNTERMINATED
TB10
2 4
WIRE
2 4
WIRE
2 4
WIRE
JP3
J2
COVER SCREWS
WARNING (19)
Disconnect main power before proceeding.
