How do I set up the relay set points on my HI 2151/30WC?

The HI 2151/30WC set point relays can be set up for one of two conditions:

Gain in weight (relay is in the de-energized state until weight increases to target) or Loss in weight (relay off until weight decreases to target).

Setting up the relay Set point for proper operation includes four settings:

1. Set point target value. Set point target value is the weight value you desire at the end of the weighing cycle.

2. Set point mode. Set point mode is the mode of weight the relay will respond to (i.e.: gross, net, etc). This is set during setting of the Set point target value.

3. Set point Preact value. Set point Preact value is the amount of compensation you need to account for in-flight material after material gate has closed.

4. Set point Dead band value. Set point Dead band value is the amount of deviation you require from the target value after the relay has changed states, before the relay resets.

NOTE: The sign of the Dead band controls the logic of the relay; negative Dead band for Gain in weight, Positive Dead band for Loss in weight. The Dead band value should be numerically larger than the pre act to prevent relay chatter.

The operation of the relay is:
Relay will energize at Set point value + Preact value.
Relay will de-energize at Set point value + Dead band value.

Example:
We are running a gain if weight application.
We want 100 lbs of gross weight.
We have 15 lbs of material in-flight after the gate closes. (gate timing)
We want the relay to stay energized until we empty the scale.

Settings:
Set point value = 100 and indicating "Gross"
Preact value = -15
Dead band value = -99
Action: At start, relay is off. Relay remains off as weight increases until it reaches 85 lbs. At 85 lbs, the relay will energize. The 15 lbs of in-flight material will fall onto the scale.  Weight now reads 100 lbs. Relay remains energized as we empty the scale. When weight decreases to 1, the relay will then de-energize.

Please review the attached tech note for additional information on using set points on your HI 2151/30WC.