31
JMNC Operating Instructions
6 Setting the Rotational Speed Monitoring Device JMNC
6.2.4
Underspeed Monitoring, Increasing the
Switch Point Delay
The switching hysteresis (switch point delay) of the rota-
tional speed monitoring device comes up to 10% of the
set switch point.
By means of the potentiometer Fine (
3
) the switch-on
and switch-off points can be reduced in 2%-increments,
thus selecting a lower rotational speed than the switch-
off point. The hysteresis between switch-on ad switch-
off point remains unchanged at 10%.
6.3
Setting the Overspeed Monitoring (without Run-up Bridging)
6.3.1
Basic Setting
Attention!
Do not press the red set button (7).
This section provides that the rotational speed
monitoring device (
9
) is already connected to a
plant. In this case you must make sure that dur-
ing the following settings the drive is not
switched off by the output relay (
16
).
Danger of electric shocks!
The mounting and the electrical connection
may only be realised by a qualified electri-
cian.
Before starting the setting, disconnect the
plant and prevent it from being switched on
again.
Item
Description
Indication/Action
1-8
Set the device according to section 6.2.3.
9
Slowly turn the potentiometer Fine (
3
) counter-
clockwise.
The switch-on and the switch-off point are
lowered by approx. 2% per increment.
10
Complete the setting according to
item 10, sec-
tion 6.2.3.
Fine
±10%
