Alarm Output-Dual 8 Amp Relays

Features Isolated Dual-Channel Contact Relay Form C contact relays rated 8 amp at 250 Vac (UL) or 8 A at 24 Vdc. Outputs derived from filtered or unfiltered signal input. Fast response time. Selectable output time delay. Multiple operating modes: - output above or below setpoint - latching or non-latching - band deviation or hysteresis around each setpoint. Setpoint setup via front panel pushbuttons or RS-232/485. Security lockout of front panel setpoint controls. Certified to UL 61010C-1 (UL mark), EN 61010-1 (CE mark), and RoHS.
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	Datasheet

Two optional plug-in setpoint controller boards are available to add control and alarm capability to  DPMs, counters and remote displays:

• A board with two Form C, 8A contact relays rated for 250 Vac or 24 Vdc.
   
• A board with two isolated Form A solid state relays rated 120 mA at 130 Vac or 170 Vdc. The solid state version is recommended for high duty cycles and low-level loads.

Operating Modes

• Operation above or below setpoint. Each relay may be individually programmed to be energized above or below a setpoint, or may be disabled.

• Latching or non-latching. Each relay may be individually programmed to operate in a latching or non-latching mode. In the latching mode, when an alarm or shutdown condition is reached, the output remains in the alarm condition until it is reset by front panel pushbuttons, via the serial interface, or via the rear connector. In the non-latching mode, the output is automatically reset when the alarm condition no longer exists.

• Band deviation mode. Each relay may be set to operate in a band deviation mode, where an alarm is generated whenever the reading is a specified number of counts above or below the setpoint. In particular, band deviation is ideal to flag an out-of-tolerance condition.

• Hysteresis mode. Each relay may be set to operate in a hysteresis mode, where turn-on occurs at a specified amount above the setpoint and turn-off occurs at the same amount below the setpoint.

• Filtered or unfiltered input. Relay action may be derived from either the filtered or unfiltered DPM input signals. Using the unfiltered signal improves response time, which is typically 17 ms for a DPM with the solid state relay board. Fast response time is one of the major strengths of  DPMs, which can digitize analog data as often as 60 times per second. Using the filtered input reduces the chance of alarm triggering due to noise.

• Provisions for signal noise. A programmable time delay and reduction of relay chatter can be achieved in the DPM by selecting 1 to 128 readings in binary steps (20 ms to 2 s) prior to updating the output. Snubber circuitry is part of the contact relay board to prolong contact life. The relay response time of counters is controlled by a selectable gate time from 10 ms to 199.99 s.

Setup

Setpoint values and deviation bands are easily entered via front panel pushbuttons or by computer via the serial interface. Security lockout of the front panel pushbuttons may be set to allow operators to view but not change setpoint values. Front panel push-button operation can also be completely disabled.

The  Weight Meter and Batch Controller offer setpoint control modes beyond those of normal meter or counter operation.