AND Weighing Indicator AD-4401, Instruction Manual

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CHAPTER 7 WEIGHING SEQUENCE
7-1 WEIGHING SEQUENCE
GENERAL DESCRIPTION
Weighing sequence, means to output control signals to the units connected to the Control I/O, etc., by means of input
signals from the load cell and external unit. In order to cope with a wide range of applications, the AD-4401 has various
weighing sequences.
The weighing sequence differs depending on the weighing mode. The AD-4401 has 8 kinds of weighing modes; four
kinds of “batch weighing” for the hopper scale and other 4 kinds of “check weighing” for the platform scale.
The weighing modes can be sorted into “customer programmed control mode” and “built-in-automatic program mode”,
depending on their operations. The following describes their difference.
Customer programmed control mode
Always compares a weight to a setpoint and outputs its result to the Control I/O.
Built-in-automatic program mode
So that a hopper scale gate can be controlled by the AD-4401 alone, the control software conventionally contained in the
PLC is now incorporated in the weighing sequence.
Loading is initiated by a batch start signal from an external unit, and when the specified weight is obtained, a gate is
closed and a loading result is judged.
The AD-4401 can also deal with a discharging sequence.
Weighing Mode CALF-14 Operation Application
1
Normal batching
(Customer programmed
control mode)
2
Loss-in-weight (Customer
programmed control
mode)
Customer
Programmed Control
mode (Real-time)
3
Normal batching (Built-in
automatic program mode)
4
Loss-in-weight (Built-in
automatic program mode)
Batch
Weighing
Mode
Built-in automatic
program mode
Hopper scale
5 Check weighing 1
6 Check weighing 2
7 Check weighing 3
8 Check weighing 4
Check
Weighing
Mode Customer
Programmed Control
mode (Real-time)
Platform scale
A sequence signal (comparison result) is output to the Control I/O. For the details of the Control I/O, see 8-1.
FUNCTIONING OF EACH WEIGHING MODE
The setpoints used in the weighing sequence are set with the keys, thumbwheel switches, and so on. The keys and
5-digit mode thumbwheel switch may be used in the same manner regardless of the weighing mode. When using the
16-digit mode thumbwheel switch, however, its digit distribution varies from one weighing mode to another. The
following describes the functioning of each weighing mode and connection of the 16-digit mode thumbwheel switch.