Additional Technical Information - WEBTEC DP130 Manual Del Usuario

Additional Technical information

Relay Output Option
The relay option contains two form C (normally open and normally closed contacts) relays. Each relay has an adjustable
high and low set point. The relays act as alarms by turning on when the value on the display is greater than the high set
point OR is less than the low set point. If the low set point is greater than the high set point, the relay turns on when the
value on the display meets both conditions; less than the low set point AND greater than the high set point.
Once a relay turns on, it stays on until the displayed value returns back across the set point "and then some". The "and
then some" is called hysteresis. Hysteresis is a programmable value that is common to both set points and both relays.
This means that a relay turns off when the display is less than or equal to the high set point minus the hysteresis value, or
when the display is greater than or equal to the low set point plus the hysteresis value. Should an overlap occur between
on and off conditions, the on condition overrides the off condition.
Analogue Retransmission Option
The optional analogue output provides linear 0-10 V and 4-20 mA signals. When the displayed value is equal to the
programmed output offset value, the output voltage is zero and the output current is 4 mA. When the displayed value is
equal to the programmed output full scale value, the output voltage is 10 V and the output current is 20 mA.
When the displayed value is between the output offset and output full scale value:
1. The output voltage = 10 (displayed value - output offset)
2. The output current = 16 (displayed value - output offset)
(output full scale - output offset) V,
(output full scale - output offset) mA + 4 mA Relays setting
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