Mitsubishi Electric MELSEC iQ-R Series User Manual page 222

NMT flying master timing parameters
• Index: 1F90H
• Subindex: 01H to 06H
Set parameters used for NMT flying master negotiation when the flying master function is used.
■Subindex 01H: Active NMT master detection timeout
Set the active NMT master response waiting time (ms).
■Subindex 02H: NMT master negotiation time delay
Set the waiting time (ms) before starting NMT master negotiation.
This waiting time is set to secure time to allow other devices to be initialized before deciding the active NMT master.
■Subindex 03H: Master priority level
Set the NMT master priority level.
Setting value
00H
01H
02H
■Subindex 04H: Priority time slot
Set a coefficient used to calculate the response time of NMT flying master negotiation with the priority level used.
Note that the setting value set for "Priority time slot" must be greater than the setting value of "CANopen device time slot" 
127.
■Subindex 05H: Node time slot
Set a coefficient used to calculate the response time of NMT flying master negotiation with the node ID used.
■Subindex 06H: Multiplex master detection cycle time
Set the interval (ms) for sending protocol messages for NMT flying master negotiation.
APPX
220
Appendix 3 Object Dictionary
Description
Priority High
Mid
Low