SK 3235.460 Speed Control Control Unit
Specifications
Model: SK 3235.460
Control: Microprocessor-controlled
thermostat
Compatibility: Rittal EC fan-and-filter units
with specified model numbers
Mounting: Snap-mounted on 35 mm support rail
(EN 50 022)
Product Usage Instructions
1. Application
The SK 3235.460 is designed for controlling and monitoring
enclosure internal temperature via fans, compatible with specified
Rittal EC fan-and-filter units.
2. Safety Instructions
Ensure proper installation to prevent interference and
malfunctions. Do not expose the unit to aggressive or flammable
substances.
3. Assembly
The unit can be easily snap-mounted onto a 35 mm support
rail.
4. Functional Description
- Temperature Control: Regulates enclosure
internal temperature based on setpoint and ambient
temperature. - Fan Detection: Automatically detects fan
outputs upon initial startup. - Monitoring/Malfunctions: Monitors temperature,
fan speed, and malfunctions with LEDs. - Electrical Connection: Follow electrical
connection guidelines for proper functionality.
5. Electrical Connection
Refer to the electrical connection section in the manual for
detailed instructions on connecting the unit.
6. Technical Data
Power: 100%
Fan Output: PI-controlled
FAQ
Q: What should I do if the fans do not operate as
expected?
A: Check the electrical connections and ensure proper fan
detection by the control unit.
Q: Can I use this unit with non-EC fan-and-filter units?
A: No, the unit is intended exclusively for controlling EC
fan-and-filter units.
Speed control EC
3235.460
Assembly and operating instructions
Contents
Contents EN
1 Application ……………………………………. 3
2 Safety instructions………………………….. 3
3 Intended use …………………………………. 3
4 Assembly ……………………………………… 3
5 Functional description …………………….. 3
5.1 Temperature control ………………………………….. 3 5.2 Fan detection …………………………………………… 4 5.3 Monitoring/malfunctions …………………………….. 4 5.4 LEDs ………………………………………………………. 4 5.5 Temperature sensor ………………………………….. 4 5.6 Scope of supply ……………………………………….. 4
6 Electrical connection ………………………. 4
7 Technical Data ………………………………. 5
8 Warranty ………………………………………. 6
2
Assembly and operating instructions speed control EC
Application
1 Application
Please do not lay the sensor and control cables
The SK 3235.460 is a microprocessor-controlled
parallel to other cables. Interference may lead to
EN
thermostat. This control unit was developed especially
malfunctions in the controller.
for controlling and monitoring the enclosure internal
The operating temperature range must be observed
temperature via fans. Up to four fans may be controlled
(see section 7 “Technical Data”, page 5).
and monitored to generate the airflow required in order The product must not come into contact with water,
to maintain a prescribed enclosure internal temper-
aggressive or flammable gases and vapours!
ature. Furthermore, energy consumption and noise
levels can be reduced by controlling the fan speed.
The unit is compatible with Rittal EC fan-and-filter units with the model numbers: 3240.500, 3240.9xx, 3241.500, 3241.9xx, 3243.500, 3243.9xx, 3244.500,
3 Intended use
The unit is intended exclusively for controlling the EC fan-and-filter units.
3244.9xx, 3245.500, 3245.510, 3245.600, 3245.8xx and 3245.9xx.
4 Assembly
The unit is simply snap-mounted on to the 35 mm
2 Safety instructions
support rail (EN 50 022).
Only use in a closed enclosure configuration. When installing the unit, observe the safety measures
5
Functional description
to EN 60 335.
The general safety precautions and provisions must be observed.
The operating instructions must be observed.
The safety instructions for enclosure installation must be observed.
The work must only be carried out by suitably trained, qualified personnel.
Before making any modifications inside or to the enclosure (such as relocating or installing new components), it is vital to read and observe the assembly instructions (plant documentation).
Any changes to the settings of the unit must only be made by trained, qualified personnel.
5.1 Temperature control
If the ambient temperature of the enclosure is below the setpoint, the control unit will regulate the enclosure internal temperature evenly to the prescribed setpoint. The current enclosure internal temperature is detected via a sensor. The actual value is compared with the setpoint (potentiometer 1). The fan speed is then controlled according to the temperature difference ascertained.
Within the temperature range “setpoint -6 K” to “setpoint +5 K”, the fan speed is infinitely variable via a PI control section. At higher temperatures, the fans will always operate at full speed. At lower temperatures, the fans are deactivated. At the lower end of the monitored
temperature range, control is based on a hysteresis of
3 K.
Power
100 %
Alarm relay
Alarm relay J8.1-J8.2 open
5 K
J8.1-J8.2 closed
Fan output PI-controlled
10 %
Fig. 1: Temperature control
Setpoint -6 K
Setpoint
Temperature
Setpoint +5 K
Assembly and operating instructions speed control EC
3
Electrical connection
5.2 Fan detection EN After switching on for the first time, the control unit will
automatically ascertain which fan outputs have fans
Sensor break/short-circuit
If a temperature sensor break is detected, the fans will run at full speed. Rapid intermittent triple flashing of
connected to them. There are applications in which
the red LED. The fault alarm relay drops out (contact
only one, two, three or four fans are connected. With
J8.1-J8.2 closed).
several fans connected simultaneously, the speed is
controlled identically for all fans (0 100%). Should a previously detected fan suddenly stop responding during operation, a warning message will be issued. If no fans at all are initially detected following commissioning, a warning message will likewise be generated.
System error
In the event of a system error, the control unit resets itself automatically. If the control unit is unable to execute the program normally, all the connected fans are set to maximum speed. The red LED is continuously
illuminated. The fault alarm relay drops out (contact
5.3 Monitoring/malfunctions
J8.1-J8.2 closed).
During normal operation, contact J8.1-J8.2 of the
alarm relay is open.
5.4 LEDs
Green = Operating voltage applied
Overtemperature
Red = Malfunction,
At a measured temperature of more than 5 K above the setpoint, temperature monitoring will cut in (see diagram). The red LED is illuminated. The fault alarm relay
see section 5.3 “Monitoring/malfunctions”, page 4
drops out (contact J8.1-J8.2 closed). The overtemperature warning is cancelled as soon as the measured temperature drops back below the setpoint.
5.5 Temperature sensor The sensor may be extended to a maximum of 50 m using a two-wire cable (suitable for 230 V); it can also
be shortened. Cable routing parallel to live cables
Fan-and-filter unit failure/line break
should be avoided, to prevent interference.
If the speed of all fans drops to zero, the fault alarm re-
lay will drop out (contact J8.1-J8.2 closed) and the red LED will flash continuously (ON/OFF for 0.5 sec. each).
5.6 Scope of supply
If there is not at least one tacho signal present and one
Qty.
Designation
set value is assigned to the fan(s), an alarm signal is triggered. Example: If 3 fans are connected and two
1
Thermostat
of these fans fail, no alarm signal is triggered by the
1
fan monitoring. However, if the temperature setpoint is
exceeded (see “Overtemperature”), an alarm signal is
1
Temperature sensor, L = 1.8 m Assembly instructions
triggered. Please note: In the event of a line break, the fan runs automatically at a fixed speed.
Tab. 1: Scope of supply
6 Electrical connection
LN
Supply Power
NLNLNLN L
Fan Power Fan Power Fan Power Fan Power
Alarm
Fig. 2: Electrical connection
Sensor
Fan 1 Fan 2 Fan 3 Fan 4
0-10V GND Speed 0-10V GND Speed 0-10V GND Speed 0-10V GND Speed
4
Assembly and operating instructions speed control EC
7 Technical Data
Model No. Operating voltage and operating current Frequency Rated impulse voltage Maximum phase to ground voltage of the supply source Environment
Classification of installation and use
Control type Software class Overvoltage category Setting range, temperature (P1) Fan speed Temperature sensor Control
Alarm
Level of contamination EMC immunity EMC interference emission Protection category Operating temperature Storage temperature Humidity Operating air pressure
Connection
Solid/Stranded conductor Solid/Stranded conductor with ferrule Mounting Enclosure Dimensions
Tab. 2: Technical Data
Technical Data
EN
3235.460 100 V 250 V/AC, < 8 mA without fan 50/60 Hz 2500 V 250 V
Indoor, open type Incorporated control intended to be used in protection class I equipment Incorporated control, panel mounting A II 5…55 °C/41…131 °F 10 %…100 % NTC, 10 k at 25 °C, 3977 K, cable 1.8…2 m PI Alarm Relay, changeover contact; Contact rating 24 V DC and 100…230 V AC, 2 A (cos = 1) load 2 IEC 61 000-6-2 IEC 61 000-6-4 IP 20 -25 °C…+55 °C -40 °C…+70 °C 10…95 % 80 kPa…108 kPa (2000 m) Spring clamp terminals 0,8…1,5 mm² (Cage Clamp terminal strip) Internal conductors the methods of connection for main supply and I/O are shown by markings and the technical sheet delivered with operating control. 0.08…2.5 mm² 0.25…1.5 mm² Onto 35 mm support rail (EN 50 022) Polycarbonate, UL 94 V-0 W x H x D: 163 x 57.6 x 90 mm
Assembly and operating instructions speed control EC
5
Warranty
Caution!
EN
If more than one EC fan-and-filter unit
is used, this is a Class A device that
causes radio interference in residen-
tial areas. In such cases, the operating
company may be asked to implement
appropriate measures. When using a
single EC fan-and-filter unit, Class B is
achieved.
8 Warranty
The conditions named in the sales and delivery conditions of the associated Rittal agents and subsidiaries apply.
6
Assembly and operating instructions speed control EC
Notes
Assembly and operating instructions speed control EC
7
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You can find the contact details of all Rittal companies throughout the world here.
www.rittal.com/contact RITTAL GmbH & Co. KG Auf dem Stuetzelberg · 35745 Herborn · Germany Phone +49 2772 505-0 E-mail: info@rittal.de · www.rittal.com
01.2025/D-0000-00004355-00
Documents / Resources
 |
Rittal SK 3235.460 Speed Control Control Unit [pdf] Instruction Manual 3240.500, 3240.9xx, 3241.500, 3241.9xx, 3243.500, 3243.9xx, 3244.500, 3244.9xx, 3245.500, 3245.510, 3245.600, 3245.8xx, 3245.9xx, SK 3235.460 Speed Control Control Unit, SK 3235.460, Speed Control Control Unit, Control Control Unit, Control Unit |