HeatNet Smith Series, User Manual

Page: 36 / 82

WIRING CONNECTIONS HeatNet Control REV 1.38-1
Page 36
Figure 29 Heating Method 3 – 4-20mA
A
C
G
N
D
1 AMP
VFD
OUTPUT
O
U
T
P
U
T
DHW PUMP/
D H W T A N K
AUX STATUS
Aux Status/
+
PUMP/VALVE
M
O
D
B
U
S
H
N
E
T
A L R M R S T
D A M P E R
H E A D E R R E T U R N S U P P L Y
P
W
M
/0
-1
0
4-
20
m
a
8
SPARE 4
LWCO
- + - + - + - + - + - +
KNSMITH R1.0
KN/F-SERIES
PUMP
1
1
1
1
1
1
8
10
1
8
8
1 1
1
1
RET
DISPLAY/KEYPAD
DAMPER
HEAT
ALARM
DEMAND
ALARM LOCAL PUMP DAMPER SYSTEM PUMP
T2 T1 OR OVR
AA LOCAL
DAMPER
SYSTEM
S Y S T E M
HI/LO NO
24
V
D
C
4 - 2 0 m A
24
V
D
C
S P A R E 2 W T R O U T O U T S ID E
0-1
0V
D
C
EXT OPERAT
VFD
WTR FLW
GAS PR
SYSTEM
24V 24V
BOILR START
24VAC TRANSFORMER
PILOT VALVE
MAIN VALVE
HIGH LIMIT
Unused
4-20ma
PWM/0-10
1
1
8
+ -
A IR
W T R I N
AIR PR SW
VALVE ALRM
FLAME SAFE
IN
TE
R
LO
C
K
S
ENABLE HIGH FIRE
R
E
T
4-20mA/
CAL
NORM
PWM
0-10
WTR FLOW
LOCAL
0-10v
A
+
B
-
G
A
+
B
-
G
A
+
B
-
G
ALARM
OPTION
S
en
se
24
V
A
C
DHW PUMP
LOW FIRE
L2
L1
L1
3
P
O
W
E
R
S
E
R
V
IC
E
L2
A
C
G
N
D
1
02-2008
OPERATOR
O
U
T
P
U
T
0-1
0V
D
C
W B R
MODULATION CONTROL
-
4-20mA
BLOWER M
IG
N
IT
IO
N
C
O
N
TR
O
L
Unused
1
1
1
1
Ju
m
pe
r 2
-3
fo
r 1
35
o
hm
2
3
HEAT NET
K 8
J2
2
J2
0
J6
D
5
D
4
K7a
T
77
_R
E
LA
Y
K7
J2
S
4
S2
SIP1
20 19
1
2
J9
F
3
J1
0B
U
26
J12A
J12B
J13
J1
0A
F
1
J4
J1
6
J18
J1
9
J1
4
K1
K4
K5 K6
K2
BZ1
JP
3
K1a
T
77
_R
E
LA
Y
K2a
T
77
_R
E
LA
Y
K4a
T
77
_R
E
LA
Y
K5a
T
77
_R
E
LA
Y
K6a
T
77
_R
E
LA
Y
J10
J1
1
J1
2
S
3
J8
J1
7
Y
1
S1
J2
1
JP4
U4
PROTOCESSOR
JP
S
1
J1
J5
A
J5
B
J3
J5
This Method allows direct modulation of the boiler based on a 4-20 mA control signal. A
control capable of transmitting a 4-20mA/0-10 VDC control signal for the purpose of
modulating a boiler and to control a common system temperature must be used with this
method.
4-20mA setpoint control functionality
This function translates a 4 to 20mA control signal to a setpoint mapped from 60F to the Max
Boiler temp. The control of the system works identically to Method 1, but allows the setpoint
to be controlled remotely. The minimum current accepted is 3.7mA and is adjustable to 5mA.
It is mapped to the 4mA setpoint in the 4-20mA INPUT menu. The maximum 20mA input
setpoint is mapped to the 20mA setpoint also adjustable in the 4-20mA INPUT menu. To get
the approximate setpoint, divide the 4-20mA current sent by .09. Example: 10ma /.09 = 110F.
The feature is enabled in the SETPOINTS menu as:
SETPT SOURCE 4-20mA
NOTE: If using a 0-10 VDC signal multiply any references to current in the manual by
.5. Example: 5ma * .5 = 2.5 VDC
Modulation Control Input
24 VDC
24 VDC Return
4-20 mA/0-10 VDC -
4-20mA/0-10 VDC +
Jumper in this
position: 4-20mA
Closing a contact
here enables the
4-20mA control
signal input.