Function Diagramm; Approvals And Markings; Applications; Function - DOLD SAFEMASTER S LH 5946 Traduction De La Notice Originale

Safety Technique
SAFEMASTER S
Standstill Monitor
LH 5946

Applications

The safe sensorless LH 5946 standstill monitor is suitable for detects
the standstill of 3-phase and 1-phase electric motors independent of the
direction of rotation. This means sensors such as encoders or proximity
switches are not required. The standstill monitor measures the induced
voltage of the coasting motor. If the induced voltage approaches 0, this
means motor standstill for the device and the output relay is activated.

Function Diagramm

U
H
A1/A2
Motor speed /
voltage
L1/L2/L3
Line breakage
L1/L2/L3
23-24
33-34
43-44
53-54
A3-ON
11-12
t
E
A3-ERR
Standstill delay time t s
Start up delay time U H
All technical data in this list relate to the state at the moment of edition. We reserve the right
for technical improvements and changes at any time.
t
Voltage level
U an
t
E
M9647_b
t =2...2,5s
E
Your Advantages
• Without sensor and safe
• Fast reaction time
• Easy to retrofit
• Combined with interlock SAFEMASTER STS
Features
• According to
- Performance Level (PL) e and category 4 to EN ISO 13849-1
- SIL-Claimed Level (SIL CL) 3 to IEC/EN 62061
- Safety Integrity Level (SIL) 3 to IEC/EN 61508, IEC/EN 61511
and EN 61800-5-2
• Safe standstill detection on 3- and single-phase motors
• No external sensors necessary
• Independent of direction
• Broken wire detection
• Forcibly guided safety contacts:
3 NO contacts, 1 NC contact for AC 250 V
• 2 semiconductor monitoring outputs
• 1 monitoring output (NO contact)
• Adjustable voltage setting
• Adjustable standstill time delay
• LED indicators for standstill, event of line breakage and
operation voltage
• Suitable for operation with inverters
• Width 45 mm

Approvals and Markings

Applications
Safe standstill detection on 3- and single-phase motors, e.g. to enable
gate interlocks on machine tools or to activate hold in brakes.

Function

The Standstill monitor LH5946 is suitable to monitor the standstill of all
electric motors that generate a remanence voltage while coasting to stop.
The LH 5946 is connected to the motor terminals and measures the
induced back emf voltage. 2 redundant measuring channels are used (L2-
L1 and L3 L1). If the back emf voltage drops to 0 simultaneously in both
channels this indicates standstill and the output relay is energized.
To adopt the unit to all different types of motors and applications the
voltage threshold indicating standstill on LH 5946 is adjustable. Also the
time delay between detection and energisation of the relay is adjustable
(standstill time ts).
In addition the unit detects broken wire on the measuring inputs
L1 / L2 / L3. If broken wire is detected the output relays goes into safe
state (as with running motor). This state is stored and can be reset by
bridging terminals X3-X2.
The input signals of both channels are permanently compared. If the
signals are different for more then 2.5 sec a simultaneity failure is detected.
This failure resets when both input channels receive simultaneous signals
with a level, above the voltage threshold and hysteresis.
To the terminals X1-X2 the feedback circuit of external contactors (used
for contact reinforcement) is connected (NC contact). If no feedback circuit
is required, these terminals must be linked. Open terminals will cause a
failure message.
19
Canada / USA
LH 5946 / 22.03.22 en / 530A