Yaskawa P7B Drive Bypass - Manual (Page 155)

Programming 5 - 61
" H3-09 Terminal A2 Function Selection
H3-09 is one of the special parameter settings required by the Bypass logic circuit. See Table 5.2.
The A2 analog input can be programmed to perform many different functions. The setting of parameter H3-09 determines
which of the following functions the A2 analog input will perform.
Function: Aux Reference
Setting: 2
In order for the A2 analog input to be used as the master Speed Command, parameter H3-09 must be set for Aux Reference
(H3-09= “2: Aux Reference”). Once A2 is configured as an auxiliary reference, it can be selected as the master Speed
Command by setting H3-13= “1: Main Fref TA2”. If H3-09= 2, terminal A2 analog input will become the speed command
when a digital input programmed for Multi-Step Ref 1 (H1-0x= 3) is selected by a contact closure.
Function: PI Feedback
Setting: B
Configuring the A2 analog input as PI Feedback (H3-09= “B: PI Feedback”) is a requirement of setting the Drive up for PI
operation. The A2 analog input is the only source for feedback for PI operation though the setpoint can come from a number of
different sources (refer to the section covering the PI parameters for more information regarding specifying the setpoint
source. PI parameters are listed in section b5).
Parameters H3-10 (Terminal A2 Gain) and H3-11 (Terminal A2 Bias) can be used to configure the A2 analog input to match
the signal from the Feedback Transmitter.
The U1-24 monitor (PI Feedback) can be used to check the PI Feedback level with the digital operator.
Function: PI Differential
Setting: 16
Normal PI operation will adjust the Drive output in order to match the measured feedback value to a desired setpoint. When PI
is operated in the differential mode, however, the Drive output is adjusted in order to maintain a desired differential between
two feedback signals.
When the A2 analog input is configured as a PI Differential (H3-09= “16: PI Differential”), the A1 analog input becomes the
other PI Differential input. The desired differential is set by parameter b5-07 (PI Differential Setpoint) and can be set so that
A2 is held less than A1 (b5-07 <0) or A2 is held greater than A1 (b5-07>0).
When PI Differential operation is chosen, the A1 feedback level can be monitored by U1-24 (PI Feedback) and the A2
feedback level can be monitored by U1-53 (PI Feedback2).
Setting Description
0 Frequency Bias
2 Aux Reference
B PI Feedback
D Frequency Bias 2
E Motor Temperature
16 PI Differential
1F Not Used