H B X S N O - 0 5 5 0 S n o w M e l t C o n t r o l
V e r s i o n 2 . 1 4 . 1
Page 4
1, 2, 3, 4, 5: Snowmelt Optical Sensor
Connection order: Green - Contact 1, Red - Contact
2, White - Contact 3, Black - Contact 4,
Shield - Contact 5.
6, 7: Demand Signal
Apply snow melt demand from a dry contact. For
force melt demand, use a momentary switch.
8, 9: Boiler Contacts
Boiler enable contact.
Sensor Inputs
10, 13:
System supply sensor- Brass strap on sensor, to
be installed on the supply to the snow melt manifold
11, 13:
Return sensor - Brass strap on sensor, to be
installed on the return from the snow melt manifold
12, 13:
Outdoor sensor - OUT-0100 install on the north
wall out of the sun and away from any exhaust vents.
Ensure that the hole for the wire is sealed.
14, 15, 16: Power Supply
Apply 120 VAC to power unit.
17, 18: Relay 1
Generally used as a system pump.
19, 20: Relay 2
Generally used as floating action valve up (Open).
21, 22: Relay 3
For injection mixing, generally used as injection pump.
For floating action mixing, generally used as floating
action valve down (Closed).
(Relays 1, 2 and 3 are dry contacts and rated
for a maximum of 5A.)
Please ensure no power is applied to pins 1 - 5
and 10 - 13.
When the desired sensor location is more than
100 feet from the SNO-0550, the sensor wire can
be extended using 18 AWG shielded cable (up
to 200 feet). The cable can be shortened if
required.
HBX
SNO-0550
Central Processing Unit
Demand Inputs
Sensor Inputs
Boiler Contacts
SNO-0110 Optical Sensor
Relay 3
Relay 2
Relay 1
Supply Power 120 VAC
5 A
RL
1
RL
18
17
1
5 A
RL
2
RL
20
19
2
GR
120
16
N
L
15
14
TM
3
2
11
TM
TM
10
12
13
BL
1
BL
9
8
1
1
5
SG
2
2
PW TM
1
3
4
5 A
RL
2
RL
22
21
2
FD
1
FD
7
6
1
5
S
4
3
C
1
2 A
5 A
5 A
Central Processing Unit
SNO-0550
HBX
5 A
RL
1
RL
18
17
1
RL
2
RL
20
19
2
GR
120
16
N
L
15
14
TM
3
2
11
TM TM
10
12 13
BL
1
BL
9
8
1
1
5
SG
2
2
PW TM
1
3 4
24 VAC MAX
RL
2
RL
22
21
2
FD
1
FD
7
6
1
5
S
4
3
C
1
2 A
DO NOT
CONNECT
POWER
HERE
DO NOT
CONNECT
POWER HERE
WIRING AND INSTALLATION
Wiring
All thermistor wiring must be with a minimum of 18AWG wire at a maximum of 500ft.
Installation
The SNO-0550 is designed to be wall mounted or installed in a separate
electrical enclosure. The unit should be mounted inside and protected from
falling water and high humidity conditions. With all the covers in place it is
designed to protect any individual from accidental electrical shock. It is not
suitable for installation in hazardous locations and should not be placed
close to any electromagnetic fields.
• Identify the four mounting holes on the SNO-0550, mark on the wall the
desired location of mounting.
• Predrill, anchor and fasten four screws for mounting.
• Hang SNO-0550 and fasten tight to desired locations
• Complete wiring connections in accordance with terminal locations.
Mounting Holes