KIERROSVAHTI valvontarele

Speed control relay - 35 mm
■ Control of overspeed, underspeed, operating rate, stopping
■ Measurement via discrete sensors - 3-wire PNP or NPN, Namur, voltage 0-30V or volt-free contact type
■ Works with either NO or NC sensors
■ Time between pulses adjustable from 0.05 s to 10 min.
■ Power-on inhibit time, adjustable from 0.6 to 60 s
■ Inhibit time can be managed via an external contact

Overview
The HSV relay controls the speed (or, more strictly speaking, the operating rate, or frequency) of a process (moving walkway, conveyor, etc.) using
discrete sensors:
- 3-wire PNP or NPN output proximity sensor
- voltage input 0 - 30 V
- NAMUR proximity sensor
- volt-free contact
It can be used to monitor under OR overspeed

Operating principle
Measurement
The monitored process cycle is the succession of pulses characterised by a signal with two states: high and low. The speed measurement is obtained by
measuring the duration of this signal, from the first detected change of state (either a rising or falling edge).
Digital signal processing avoids the problem of disparity of signals.
From energisation, or after the appearance (or reappearance) of the sensor signal, detection (characterisation) of the signal requires processing of one or
more periods (two maximum).
During this time, control is inoperative.

Operating mode
Using the selector switch, select one of four modes:
- Underspeed without latching
- Underspeed with latching
- Overspeed without latching
- Overspeed with latching
If, on energisation, the switch is placed in one of the three intermediate positions (between "underspeed with latching" and "overspeed with latching"), the
relay stays in the rest state ("alarm") and the error is signalled by all three LEDs flashing simultaneously.
The mode selector switch position is taken into account on energisation.
Modifications made during operation will have no effect: the active configuration may therefore be different from that indicated by the switch, the relay
operates normally but the change in configuration is signalled by all three LEDs flashing simultaneously.

Latching
In "memory" mode, when a fault has been recorded, the HSV relay latches in the rest position ("alarm" operational state). Once the speed is correct
again, the relay can be unlatched (reset) by closing contact S2 (for 50 ms minimum).
Irrespective of the speed of the controlled process, when S2 is closed the HSV relay is inhibited, the output is at the operating point ("normal" operational
state) ; if the speed is still not correct when contact S2 is reopened, the relay latches again in the rest position ("alarm" operational state).
The HSV can also be reset, by switching off and on again several times in succession (the power break must last at least 1500 ms).
If the process speed is incorrect, this method is limited by the same restriction as resetting using S2.