SC-HVAC system 3x37,5A-BM (star-delta-starting)

Wilo-Smart Controller for digital, stepless power control of one-pump and multi-pump systems in heating, air conditioning and ventilation applications.

SC version: for the control of conventional fixed speed pumps via contactors (cascade connection).

Hardware

Fully electronic Wilo-Smart Controller (SC) in sheet metal enclosure (colour: pebble grey), comprised of internal power supply, microprocessor with “Soft PLC”, analogue and digital inputs and outputs, LCD display (backlit) for displaying operating data, control parameters, operating states of the pumps, error messages and history memory. LEDs for display of system status (operation/fault), setting of operating parameters and acknowledgement of fault messages via Green Button Technology, lockable main switch, potential-free contacts for SBM/SSM collective operation and collective fault signals, contacts for external On/Off and 2nd setpoint, conductivity test in the sensor cable. Fuse protection of pump motors: By motor protection switch in the direct starting version; by fusible cut-out in the star-delta-starting version in combination with thermal triggers. Contactors for switching on the pumps; star-delta-starting models include thermal triggering and a time relay for the star-delta combination. Actual value output via analogue signal 0-10 V for external measurement/display possibility, 10 V corresponds to the sensor end value, input 0/4-20 mA for external setpoint adjustment. Automatic, load-sensitive cut-in from 1 to n peak-load pump(s) depending on the control variables

• Pressure - constant, p-c
• Differential pressure - constant, dp-c
• Temperature setter, n = f(Tx)
• Differential pressure - constant, dT

Software functions

Fully automatic control for 1 to n pumps by means of setpoint/actual value comparison, 4-20 mA sensor signal (conductivity test) for control variable actual values, menu navigation with symbols and menu numbers.

2 parameter sets can be selected: Easy Menu (setpoint & control mode) or expert Menu (operation and control parameters)

Can be selected by Customer Service with or without standby pump, automatic switching of an operating pump to the reserve pump in the event of a fault, operating mode of the pumps can be selected freely (manual, off, automatic), elapsed time indicator for each pump and system, switching cycle counter for each pump and system.

Monitoring of Max. and Min. values of the system with adjustable delay times and limits, external On/Off via contact for deactivation of the Automatic mode of the system, fault memory of the last 16 faults, setpoint switching of 2nd setpoint can be activated by contact, SBM and SSM logic reversal possible, parameters pre-set at the factory for simple commissioning.

Automatic, configurable pump cycling

• Standard setting: Impulse - The base-load pump is cycled at each new demand, regardless of operating hours
• Alternative: Pump cycling dependent on operating hours, cycling of the base-load pump after the specified operating hours

Automatic pump trial run (pump kick)

• Can be activated
• Time between two pump trial runs is freely programmable

Standards followed

• Electrical Equipment of Machines EN 60204-1
• Low-voltage switchgear combinations EN 61439-1 and 61439-2
• EMC - Interference immunity for Industrial Environments EN 61000-6-2
• EMC interference emission for domestic accommodation, trade and commercial premises and small companies EN 61000-6-3 (for SC-FC only to 7.5 kW, over this EN 61000-6-4 interference emission industrial premises)

Extra charge for optional modules for connection to BMS and bus systems (installation at the factory or subsequently after technical clarification):

• H-0-A (Manual-Zero-Automatic) switch: preselection of the operating mode of each pump and manual operation in the event of a controller fault “Manual” (emergency/test mode available at mains power, motor protection available), “O” (pump switched off – cannot be switched on using the controller) and “Auto” (pump enabled for automatic mode via the controller).
• Evaluation relay for PTC
• Individual running and fault signals
• Converter 0/2-10 V in 0/4 to 20 mA
• Soft starter for peak-load pumps
• Connection to BMS systems in accordance with VDI 3814
• Bus systems: BACnet, LON, Modbus RTU

Scope of delivery

• Switchgear
• Installation and operating instructions
• Circuit diagram