Manual Supplement
Rosemount 5300/5400 Series
External HART Devices (Slaves)
The HMC supports up to four external HART devices. The external devices are separated by using the HART address. The address must be different between the external devices and only addresses 1 to 5 are allowed for multiple slaves. Connect the devices one at a time and change the short address prior to connecting the next device by using a HART Configuration Tool such as RRM, or a Field Communicator.
NOTE
The power supply from the HMC to external HART devices is not intrinsically safe. In a hazardous environment, any external HART device connected to the HMC must have
The HMC cyclically polls the HART devices for measurement values. The update rate depends on the number of connected devices and is shown in Table
Table
No. of devices | Approx. update rate | |
(slaves) | ||
| ||
1 | 2 seconds | |
2 | 3 seconds | |
3 | 4 seconds | |
4 | 5 seconds | |
5 | 5 seconds |
Figure 1-7. The HMC Module supports up to four external devices (slaves)
RS-485
Bus
Power Supply
Up to four external devices
HART to Modbus Converter
MB
MODBUS MA
- POWER +
| HART Ambients > 60 ºC |
+ | Use wiring rated |
for min 90 ºC |
External HART |
| External HART |
device 2 |
| device 1 |
|
|
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