VARIABLE SETPOINT OPTION

TM 5-3895-374-24-1 GP470FA 4. Press [FUNCTION DISPLAY] to exit the setup mode and return to normal operation. I. VARIABLE SETPOINT OPTION On open fired systems such as the Hauck StarJet burner, the dryer draft setpoint is a critical factor in controlling the amount of excess air in the system. The variable setpoint option adjusts the DPS controller’s setpoint in response to the burner firing rate. For example 0.05" wc draft may be sufficient at low fire while 0.30" wc draft may be required for proper operation at the burner’s maximum firing rate. As shown in figure 6, the DPS may be configured to automatically increase its setpoint from -0.05" to -0.30" as the burner control motor moves from 0 to 100% output. Fig . 6 The main component of the variable setpoint option is a signal converter module which plugs into a pre-wired socket in the controller assembly. By connecting DPS terminals 22 and 23 to terminals 22 and 23 of a Hauck BCS burner control system, the burner control motor slidewire feedback signal will be converted to a 4-20mA remote setpoint input signal for use by the DPS controller. The following procedure details the DC200E controller configuration required to accommodate the variable setpoint operation. 1. Press [SET UP] until the display reads SET UP ALGOR. 2. Press the [FUNCTION] key until the lower display reads INPUT2. 3. Press the ] key to change the upper display to ENAB. (page 3-44)