R&M Materials Handling HOIST MONITORS - Manual (Page 52)

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Springfield, Ohio 45502
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10 Overload protection – Load sensor
10.1 Load sensor-system
The load sensor-system uses the analogue signal coming from a load sensor. The sensor can be either a
Strain-gauge type, or a Hall-sensor type.
The Strain-gauge type of sensor is the default solution in hoists. The Strain-gauge type will give out a
signal in the range of 0…40mVDC. To amplify this signal, a load sensor amplifier must be connected
between the sensor and the hoist-monitoring unit. The instructions on how to set up the amplifier are
included in chapter “Load sensor adjustment” of this manual.
The Hall-sensor type was commonly used in XL-hoists. The Hall sensor gives out a signal in the range of
4…6VDC, which can be fed directly into the hoist-monitoring unit.
Other sensor types are possible to use if the load sensor gives out a signal in the range of 0V to
8V.
10.1.1 Load sensor set-up
Follow the instructions given in the section “Load sensor adjustment” of this manual.
10.2 Load sensor parameters
Parameter Value Description Note
4-7
Load param Load calculation menu Accessible with password 4: 8124
4-7-1
Load meas. Sens. Selects the load sensor measurement method
Parameter Value Description Note
6
Design In this menu are the mechanical design values of the
hoist determined. Accessible with password 6: 9822
6-4
Nom. Load 0.00- 999t Rated load of the hoist. Setting according to the data label of the hoist
In case the automatic load calibration sequence does not give the required results (i.e. the difference
between the actual load and the calculated/displayed load is more than 10%), the unit can be calibrated
manually with the following parameters. Refer to paragraph “Manual load calibration” of this chapter for
further instructions.
Parameter Value Description Note
3-4
SC values Load calibration values for the load sensor method Accessible with password 2: 0732
3-4-1
Load 1 25.0t The higher test load value (80% – 130%) × Hoist
nominal Load [tons]
3-4-2
Input 1 7.23V The load measurement voltage in the analogue input
Ain1 corresponding to the test load
3-4-3
Load 2 0.00t The lower test load value, usually the empty hook 0.00t
(0% – 30%) × Hoist nominal Load [tons]
3-4-4
Input 3 2.07V The load measurement voltage in the analogue input
Ain1 corresponding to the load 2