Nova Electronics MCX514, Руководство пользователя

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NOVA electronics Inc. MCX514 -
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Example 2 Home search using a limit signal
The example that uses a limit signal of one side as an alternative home
signal and performs a home search. In this case, a limit signal in the
－
direction is used as an alternative home signal. To perform a home
search by using a limit signal, the following two conditions are applied.
Fig. 2.5-15 Connection of Example 2 Automatic Home Search
a. When high-speed search operation in Step 1 is performed, decelerating stop must be done sufficiently within the
distance from the limit signal activation position to the mechanical limit position.
b. The automatic home search position is not beyond the limit signal active section in the search direction (B in Fig.
2.5-16).
The operation steps of an automatic home search in this case are shown in the table below. The mode setting in Steps 1 and 2,
when a search direction is specified in the
－
direction and a limit signal is specified as a detection signal, the limit signal of the
－
direction is determined (nLMTM).
Table 2.5-13 Automatic Home Search Example 2 Operation
Step Operation
Execution/
Non- execution
Detection
signal
Signal level Search direction Search speed
１
High-speed search Execution
nLMTM
Low active
－
direction 20,000pps
２
Low -speed search Execution
－
direction 500pps
３
Z-phase search Non- execution
－ － － －
４
Offset drive Execution
－
－ ＋
direction 20,000pps
The operation from Step 1 to Step 4 is the same as the operation using a home
signal (nSTOP1) described above.
When the automatic home search starting position is in point A as shown in the
right side figure, the function performs irregular operation
①
of Step 2
without executing Step 1. And it escapes in the reverse direction from the limit
signal active section once, and then search operation is performed in the
specified direction.
Fig. 2.5-16 Operation of Example 2 Automatic Home Search
【
Program Example in X axis
】
// WR2 Register setting
WR0
← 011Fh Write // Select X axis
WR2 ← 1800h Write // Limit signal logical setting ： XLMTM:Low active
// Enables hardware limit Decelerating stop Note1
// Input signal filter mode setting
WR6
← 0A0Fh Write // D11 ～ D8 1010 Filter delay:512 μ sec
// D1 1 XLMTM signal ： Enables the filter
WR0 ← 0125h Write // Writes a command
// Automatic home search mode setting 1
WR6
← 807Bh Write // D15 1 Step ４ execution/non-execution ： Execution
// D14 0 Step ３ LP clear Disable
// D13 0 Step ３ RP clear Disable
// D12 0 Step ３ DCC output ： Disable
// D11 0 Step ３ search direction ： －
// D10 0 Step ３ execution/non-execution ： Non-execution
// D9 0 Step ２ LP clear Disable
// D8 0 Step ２ RP clear Disable
// D7 0 Step ２ DCC output ： Disable
// D6 1 Step ２ detection signal ： LMTM
// D5 1 Step ２ search direction ： － direction
// D4 1 Step ２ execution/non-execution ： Execution
// D3,2 1,0 Step １ detection signal ： LMTM
－
direction
Over Run Limit
nLMTM
MCX514
Photo
Coupler
nLMTM
Step1
Step2
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Search
Direction
Active
Section
Over Run Limit in the
Search Direction