Myron L 729II - Manual (Page 52)

48
A. PRIMARY COMPONENT IDENTIFICATION
As identified in Section III, the Monitors/controllers switch(es)
and indicator components are mounted directly to the front panel.
The Monitor/controllers main circuit board is contained within and
mounted to the back of the enclosure. Some models with options
have an additional circuit board mounted behind the front panel,
i.e. Model 723II-4A (4-20 Module).
Review figure V.A.1 below to familiarize yourself with the Main
circuit board assembly. The following diagram has the second
alarm/control module option installed.
V. COMPONENT IDENTIFICATION,
CALIBRATION AND PREVENTIVE CARE
{
POWER
AC LINE/ +DC
AC NEUTRAL/ -DC
GROUND
Figure V.A.1
SPAN ZERO
DO NOT
ADJUST
RELAY #1
}
COM
NC NO
3SO/3SE
SWITCH
CONNECTION
DISPLAY/METER
CONNECTOR
4-20 CONNECTOR
SET POINT #1
CONVERSION
TRANSFORMER
FUSE*
115/
230
ZERO
CALIBRATION
CONTROL
SET POINT #2 CONTROL
SC/SCO
OPTIONAL
SECOND
ALARM/
CONTROL
MODULE
SET POINT #2
CONVERSION
#2 RELAY
LIGHTS &
SWITCH
CONNECTOR
DISPLAY CALIBRATION
CONTROL (FACTORY SET)
RUBBER TAPE
(DO NOT
REMOVE)
SPC
INC
PA
SET POINT
#1 CONTROL
INC
SET POINT #1
HYSTERESIS
RIGHT INC
LEFT DEC
CHASSIS GROUND - OEM
INC
SET POINT #2 HYSTERESIS
RIGHT INC / LEFT DEC
3S
SPC
0-10VDC OUTPUT
B
L
K
W
H
T
R
E
D
G
R
N
N
E
U
(+) SENSOR
(-)
+
COM
RELAY #2
}
NO
NC
+
SPAN (GAIN)
CALIBRATION
CONTROL
721 726
722 727
723 728
724 729
MYRON L
COMPANY
7 pH/ZERO mV
PUSH TO TEST
SPAN (GAIN)
PUSH TO TEST
CONFIGURATION
MODULE
CONFIGURATION
MODULE
ALIGNMENT
ORP ZERO CALIBRATION
CONTROL (FACTORY SET)
SOLID STATE (24VDC 30mW) OUTPUT
PA™ PIEZO ELECTRIC ALARM OR
RA™ REMOTE ALARM OR
CUSTOMER CONNECTION
SOLID STATE (24VDC 30mW) OUTPUT
PA™ PIEZO ELECTRIC ALARM OR
RA™ REMOTE ALARM AND
CUSTOMER CONNECTION
HYS1 SP1 ZERO
DIS
ORP ZERO
UP
BK WT RD GN NU R- R+
PWR C GD NC NO CM
Flow Switch
RA
PA
CM
N
O
N
C
DE
C
pH
SP
AN
REMOVE T
O INST
ALL
SECOND RELA
Y
}
GN
D
CH
S