The Stock Fairfield® RoCon© Control Unit monitors the rotation of the tension end shaft, and detects when the shaft slows or stops rotating. If the chain breaks during operation, the RoCon© signals the control system to stop the machine, preventing the chain from piling up inside and causing damage.
The RoCon© works by attaching a rotor to the shaft to be monitored. The passage of the rotor blades is registered by an intelligent proximity sensor. If the blades pass the proximity sensor above the set frequency (on site adjustable), then the sensor conducts and an output signal is sent to the control system. If the blades pass below the set point then the sensor no longer conducts and there is no output signal. To allow machines to run up to speed, units with a start up delay are available.
| Switchable Speed Range | Sensor Target | Pre-Set to Activate at | Start-up Delay | Part No. | |
| STANDARD Generally available on 3 days despatch |
Low : 0.8 to 24 High : 24 to 720 |
5 Bladed | 0.8 Rev/min* | Yes 10 sec |
045/2080/01 |
| Units available on request | Low : 0.8 to 24 High : 24 to 720 |
5 Bladed | 0.8 Rev/min* | No | 045/2080/11 |
| Low : 0.4 to 12 High : 12 to 360 |
10 Bladed | 0.8 Rev/min* | Yes 10 sec |
045/2081/01 | |
| Low : 0.4 to 12 High : 12 to 360 |
10 Bladed | 0.8 Rev/min* | No | 045/2081/11 |
* On request units can be supplied to activate at any stipulated speed within its stated range.
Foot Mounting Bracket : 045/2009
Shaft Conversion Guard : 045/2033
Rotation/ no rotation detection of a shaft. In the event of machine failure the RoCon© provides a control signal to stop and protect the machine. Used within single or multiple machine control systems.
Sequence interlocking at start-up ensures each machine in series is running before the preceding machine starts.
Automatic emergency shut down. The emergency stopping of one machine fitted with a RoCon© is signalled enabling preceding machines to be stopped so preventing a cumulative breakdown.
A self-contained sensor is employed to sense blades on a target rotor mounted on the driven shaft.
Switching occurs when the frequency of the blades passing the sensor corresponds to its threshold frequency. On dropping below the threshold the sensor de-activates.
The unit operates on a digital principle, the response time being proportional to speed, i.e. the higher the speed the shorter the response time.
The housing is moulded from corrosion resistant glass reinforced polyester resin. Color Orange.
Enclosure protection it to IP657 to BSEN 60529 – temperature range – 25 to + 70 degrees centigrade and complies with temperature class T6 to BS 4683 also IEC 79.8
Allows a machine to ‘run up to speed’. If normal running speed is not achieved within 10 seconds the sensor switching current is interrupted.
Pre-set to activate at the minimum speed of 0.8 rev/min.
Adjustable on site. (On request units can be supplied to activate at a specified speed).
Without start-up delay for use with relays, timers and PLC’s in automatic control circuits.
Low speed range. Used in conjunction with a 10 bladed sensor target, a selectable speed range of 0.4 to 360 rev/min is available – full details are shown under ‘Available RoCon© Units’ in the summary.
Pre-set switching speed units can be supplied to activate at any speed within the range.
Special units for hazardous areas can be supplied for use with client's approved speed monitor to form an ‘Intrinsically Safe System’. The RoCon© details provided within this leaflet Do Not Apply. Call Stock Fairfield.
 |
|
Part Order No. 0048/3048.
Type: M300222B Baseefa03ATEX0674X 
II 1D T100°C Tamb −15 to +50°C IP65 1180
The RoCon© is wired in series with the stop push button and when operated the RoCon© conducts for 10 seconds to allow the machine to run up to speed. After 10 seconds the machine rotation maintains the RoCon© in conducting state. If the machine speed drops below the switching speed the RoCon© will cease conducting thus releasing the machine starter.
Units are normally used with relays, timers and PLC’s in automatic control circuits. Relay connection to the RoCon© will energize when the machine reads the pre-set speed and will release in event of underspeed. RoCon© can also be used to detect overspeed and a typical circuit is shown.
| WARNING: Should the starter coil load be greater than the unit rating an interposing relay must be used or damage to the sensor will occur. |
Most installations require machines to run up to speed and the standard RoCon© (ref 045/2080/01) has a 10 second delay to allow for this. If a delay is to be programmed into the PLC then the version of the RoCon© without an inbuilt delay (ref 045/2080/11) should be used.
Inputs to industrial PLC’s fall into three categories:
a) AC input
b) DC PNP input
c) DC NPN input
The two wire sensor in the RoCon© is directly applicable to the AC input PLC providing the 20mA sensor switching current is exceeded and the 1.6mA leakage current does not inhibit the OFF state of the PLC input.
For DC input PLC’s a 1k ohm, 1.5 watt ‘bleed’ resistor should be wired at the PLC according to the diagrams below.
On request a suitable resistor can be supplied free of charge.
Operating Voltage 24–240V AC/DC
Switching Current MAX 200mA
MIN 20mA
Inrush Current 2A (Duration 20mS, 3 aps/s)
Voltage Drop <8V (ON state)
Leakage Current <1.6mA (OFF state)
Speed Ranges 4–120–3600 imp/min
Override Period 10 sec (Nominal)
(units 045/2080/01 & 045/2081/01 only)
Temperature Range −15 to +50°C
Protection Rating IP65
| WARNING: damage to the sensor will result if the maximum switching current is exceeded. Always wire a load in series with the sensor. |
A 20 × 1mm torque restraining strap 200mm long is provided, this can be cut, drilled, bent and positioned as required. A reversible foot mounted bracket can be supplied as extra. Two holes tapped M5 provided on the face of RoCon© are for attachment of these items.
Nett weight 1.1kg, gross weight 1.4kg. Carton size 21 × 17 × 16cm.
At any angle, in any plane, and should be protected with the suitable guard if its position is vulnerable. Installation close to strong magnetic AC fields must be avoided.
The RoCon© is screwed into an M12 tapped hole in the end of the shaft to be monitored. On drilling in, take care that the tapped hole is coaxial with the shaft, important with higher speeds. A light flexible strap is normally used to prevent the unit from rotating, two tapped holes being provided for its attachment. The holes may be used to mount the unit on a simple fabricated bracket where a spring rope or elastic rubber belt drive is employed.
The drive torque is small so the belt tension should also be small since the overhang load on the RoCon© shaft must be minimal.
No maintenance is required, the bearing and sensor being sealed units. In the event of accidental damage replacement sensors can be supplied or the complete housing and rotor assembly (if the sensor can be re-used).
© 2007-2010 Stock - Schenck Process Group
