Fan Coil Unit Controller (FCU Controller)
SMC53-MYRM (SMC53UL020401)
Please Read Before Installing
Important Notice:
• Electrical equipment should be installed, operated, serviced, and maintained only by
qualified personnel.
• All pertinent state, regional, and local safety regulations must be observed when installing
and using this product.
Input Characteristics
• Power supply (not isolated):
- 12-24 V~ 50 / 60 Hz, 24 V-, +/- 10%, Listed Class 2, LPS, or SELV limited energy
supply <15 W
• Analog Inputs: (2) Thermistor inputs
- Type: NTC (103 AT)
- Value: 10 K at 77 ˚F (25 ˚C)
- Range: -58 ˚F to 212 ˚F (-50 ˚C to 100 ˚C)
- Resolution: 0.18 ˚F (0.1 ˚C)
- Accuracy: 1% full scale
Output Characteristics
• Relay Outputs: (5) SPST relays, Normally Open rated for:
- Resistive Max. 2 A at 24 V~ / 100 V~ / 120 V~ / 220-240 V~
- 2 FLA / 12 LRA at 100 V~ / 120 V~ / 220-240 V~ motor load
WARNING: Fire Hazard. May result in Serious Injury or Death. Do not connect the power
supply to line voltage. Do not connect the relay outputs to any other voltage not specified
by the present document.
Important Notes
• Purpose of the control: Operating Control
• Construction of control: Independently mounted for panel mounting
• Type of action: Type 1.C.
• Do not disassemble, repair, or modify this equipment
• Housing: PC+ABS UL94 V-0 resin plastic casing
• IP20 Rating
• Ambient operating temperature: −4 °F to 122 °F (−20 °C to 50 °C)
• Storage temperature: −40 °F to 185 °F (−40 °C to 85 °C)
• Operating and storage humidity: 0 – 90% relative humidity, non-condensing
• Pollution degree 2
• Insulation material group: Class IIIa material
• Over-voltage category: Class II device
• Rated impulse voltage: 2500 V
• Fire resistance: Class D
• Software: Class A device
• Maximum power consumption: 4 W / 6 VA or 5 power draw units (PDU) on the QS link. For
complete information, see the Power Draw Units on the QS Link spec (Lutron P/N 369405) at
www.lutron.com
WARNING: Electric Shock Hazard. May result in Death or Serious Injury. Do not
connect the common connection of the power supply/transformer supplying this
equipment to any external ground (earth) connection. Do not connect any common
connection or ground (earth) of the sensors and actuators connected to this equipment to
any external ground connection. If necessary, use separate power supplies/transformers
to power sensors or actuators isolated from this equipment.
Intended Use
• The products described or affected by this document, together with software, accessories, and
options, are controllers, intended for commercial HVAC machines according to the instructions,
directions, examples, and safety information contained in the present document and other
supporting documentation.
• The product may only be used in compliance with all applicable safety regulations and
directives, the specified requirements, and the technical data.
• Prior to using the product, you must perform a risk assessment in view of the planned
application. Based on the results, the appropriate safety-related measures must be
implemented. Since the product is used as a component in an overall machine or process, you
must ensure the safety of persons by means of the design of this overall system.
• Operate the product only with the specified cables and accessories. Use only genuine
accessories and spare parts.
• Any use other than the use explicitly indicated in the present document is prohibited and can
result in unanticipated hazards.
Unintended Use
• Any use other than that expressed in the present document under Intended Use is strictly
prohibited.
• The relay contacts supplied are of an electromechanical type and subject to wear. Functional
safety protection devices, specified in international or local standards, must be installed
externally to this device.
Environmental Conditions
• This equipment must be protected against dripping water or any other liquid water exposure.
The humidity level must be maintained below 90% and without condensation. Further,
installation under cold surfaces must be avoided as it can generate dripping water caused by
condensation. Use of an unventilated enclosure in a high humidity environment may increase
the risk of water damage to the controller.
• This equipment must be protected against insertion of dust or any particulate material the size
of 0.47 in (12 mm) or less.
WARNING: Fire Hazard. May result in Death or Serious Injury. Equipment must be
protected from outside elements. Install and use this equipment in non-hazardous
locations only.
®
041727 Rev. A
10/2019
Step 1: Mount the FCU Controller
WARNING: Electric Shock Hazard. May result in Serious Injury or Death. Disconnect
all power sources before installing or servicing this unit.
The FCU controller must be installed in a listed NEMA Type-1 enclosure or IP20 rated enclosure with
conformance to the IEC 61439-3 (or equivalent standard). Enclosure must meet the minimum clearance
requirements. Enclosure should be secured by a keyed or tooled locking mechanism.
• The controller can be either surface- or DIN rail-mounted. The preferred installation is DIN rail
mounting and requires a 4 DIN wide mounting location.
• All pertinent state, regional and local safety regulations must be observed when installing and
using this product.
• Use of metal enclosures to improve electromagnetic immunity of the controller system is
recommended.
1
Acceptable DIN Rail Dimensions
All dimensions shown as: in (mm)
0.59
(15)
0.22
(5.5)
0.06
(1.5)
0.04
(1)
Minimum Clearances
The FCU controller must be installed in an enclosure with the clearances shown below.
All dimensions shown as: in (mm)
Note: Controllers must be mounted horizontally on a vertical plane as shown in the figure below.
Step 2: Wire the thermostat / FCU controller communication link
The FCU controller comes with a 3-wire harness in the LR-HVAC-WIRE-100 package. Connect this
harness to the top left connector on the FCU controller. Run wires to the 3-pin connector on the
thermostat. The 3-wire harness can be extended up to 500 ft (153 m) using one 18 AWG (1.0 mm
and 1 pair 22 AWG (0.5 mm
drain / shield wire to earth / ground or to the thermostat and do not allow it to contact the grounded wallbox.
Best Wiring Practices
• I/O and communication wiring must be kept separate from the power wiring. Route these two
types of wiring in separate cable ducting.
• Verify that the operating conditions and environment are within the specification values.
• Use proper wire sizes to meet voltage and current requirements.
• Use copper conductors (required).
• Use twisted pair, shielded cables for analog signals.
Thermostat / FCU Controller Communication Link Wire Sizes (check compatibility in your area)
Wiring Length
< 500 ft (153 m)
Thermostat / FCU
controller communication
link
3
2
0.04
(1)
1.38
1.46
1.38
(35)
(37)
(35)
0.28
0.06
)
(7)
(1.5
0.59
(15)
0.8
(20)
3.4
(87)
0.3
(7.6)
2.75
0.7
(70)
(17.8)
) twisted, shielded cable. See table and diagram below. Do not connect the
2
Wire Gauge
Common (COM [G]); One 18 AWG (1.0 mm
Data (MUX and _); One twisted, shielded
pair 22 AWG (0.5 mm
)
2
4 3 2 1
English
0.8
(20)
2.4
(61)
0.8
(20)
)
2
Lutron Cable Part Number
)
2
GRX-CBL-346S (non-plenum)
GRX-PCBL-346S (plenum)