Delta Faucet NANOTRACE DF-745 - Manual (Page 37)

Connecting to External Devices DF-745 33
The 4-20 mA analog output correlating to the front panel display reading is provided on the
rear of the analyzer through connector J4. This output is electrically isolated from all other
analyzer outputs, and from chassis (Earth) ground.
The maximum load resistance for each is 1K Ohms and the analyzer provides a compliance
voltage of approximately 28 VDC.
6.4 Relay Ports – J8, J9
Four form C (SPDT) relays (contact closures) are provided to assign to the various alarms.
The contacts are rated at 30 VDC, 1A. They are not designed to switch AC power.
The relay contacts can be programmed through the user interface for up to four moisture
levels, temperature, moisture cell diagnostics, zero calibration in progress, analyzer off line,
freeze of analog outputs during calibration.
The relays are wired for Fail Safe operation such that a Normally Open (No alarm) contact
connects to common when an alarm occurs or when power to the instrument is lost.
The relay wiring can be tested with the Relay test routine found on page 57.
Pin # Moisture Relay Description
J8-8 GND Ground
J8-7 RLY2-NC Relay 2 Normally Closed
J8-6 RLY2-NO Relay 2 Normally Open
J8-5 RLY2-COM Relay 2 Common
J8-4 RLY1-NC Relay 1 Normally Closed
J8-3 RLY1-NO Relay 1 Normally Open
J8-2 RLY1-COM Relay 1 Common
J8-1 KEY Unused
J9-8 GND Ground
J9-7 RLY4-NC Relay 4 Normally Closed
J9-6 RLY4-NO Relay 4 Normally Open
J9-5 RLY4- COM Relay 4 Common
J9-4 RLY3-NC Relay 3 Normally Closed
J9-3 RLY3-NO Relay 3 Normally Open
J9-2 Key Unused
J9-1 RLY3-COM Relay 3 Common
Table 5: Pin-Out of Relay Connectors J8 and J9