ProMinent Aegis-II, Руководство по сборке и эксплуатации, Страница: 43 / 102

Mounting and Installation
Page 43 of 102
6.3.14 Dual 4-20mA Input Driver
The dual 4-20mA input card can handle active and passive loops. Both inputs are isolated from each other and the
motherboard.
Any 4-20mA input is acceptable; however, there is no square root operation for older flow meters as found in some boiler
rooms. (We have never provided this service.)
Enter any engineering units for the range. 4mA does not have to be 0.
Maximum load per loop is 50mA. Short circuit proof at 70mA. Reactivation after 10 seconds. ProMinent recommends a
maximum length of 1,000 feet using 22 AWG wire or larger. Twisted, shielded, stranded cable is best for long distances.
Figure 54 Dual 4-20ma
Input driver
6.3.15 Connection of Amperometric Sensors
ProMinent amperometric sensors can be terminated to a 4-20mA input driver card.
Connect the sensor, as described in section
6.3.14 Dual 4-20mA Input Driver
Note:
if connecting a non-powered sensor to G input you will need to use 15VDC power supply from either one of the digital
inputs or an external power supply. If power is pulled from a digital input, the digital inputs will no longer be isolated from 4-
20mA input G, since they are sharing the same power supply. For this reason, we will not use the G input for Prominent
amperometric sensors. A toroidal conductivity probe or EcoPod level sensor will work.
Figure 53 Dual mA Input Driver Connections
Table 10 Dual mA Input Connections