Hitachi WJ C1 Series User Manual

Chapter 9 Inverter Functions
9-5-17
Protection function when using encoder feedback
 When encoder feedback is enabled, the following protective functions are available. Please use
according to the intended application.
Code
Item
Description
Data
[P015]
Creep speed
Low operation speed before positioning in
simple position control is complete, and the
speed of encoder disconnection detection
judgment.
Minimum frequency [b082]
to 10.00 (s)
[P026]
Over-speed
detection level
A trip will occur with an "Overspeed error
[E081]" if the feedback detection speed
exceeds the over-speed detection level
multiplied by the maximum frequency setting
when [P003] = "Speed feedback (01)".
This setting is disabled if this is set to 0.0.
0.0 to 150.0 (%)
[P027]
Speed
deviation error
detection level
Sets the level at which excessive speed
deviation is detected.
0.00 to 120.00 (Hz)
[P077]
Encoder
disconnection
timeout
Sets the time to detect an encoder
disconnection. Disconnection detection is
disabled if this is set to 0.0.
0.0 to 10.0 (s)
[C021]
[C022]
[C026]
Output terminal
function
Speed over deviation [DSE]:
The [DSE] signal turns on when the
following conditions are met during
operation.
| [d001] - [d008] | ≧ [P027]
22
■ Over-speed error detection
 If the feedback detection speed exceeds the "Over-speed detection level [P026]", the inverter
will trip with an "Overspeed error [E81]". Set this to the maximum speed of the intended
application.
This function is enabled when "Pulse input, target function selection [P003]" is set to "Speed
feedback (01)", and [P026] does not equal 0.0.
■ Speed deviation error detection
 If the absolute value of speed deviation (output frequency - feedback detection speed) equals or
exceeds the "Speed deviation error detection level [P027]" during operation, the " Speed over
deviation [DSE] (22)" output turns ON. The inverter does not trip at this time. To enable this
function, assign the [DSE] terminal to the output terminal, and set [P027] to a value other than
0.00.
■ Encoder disconnection detection
 If the output frequency equals or exceeds the "Creep speed [P015]" and the feedback detection
speed is less than the "Minimum frequency [b082]" for the duration of the "Encoder
disconnection timeout [P077]", the inverter will trip with an "Encoder disconnection error [E80]".
If a false detection occurs due to heavy loads and a slow startup, adjust [P015] and [P077]
according to the intended application.
A

Hitachi WJ C1 Series Specifications

General

Brand	Hitachi
Model	WJ C1 Series
Category	Inverter
Language	English