The A1P is a proportional, infinitely variable power controller capable of delivering 0-97% of the applied line voltage to the directly connected electric heaters. The A1P will not control transformers or motors. This is accomplished by phase angle firing a pair of inversely connected SCR's. Modular construction allows for simple and solderless field serviceability. There are four field replaceable items:
- Printed circuit board
- Fuse
- Dual SCR package
- MOV (metal oxide varistor)
Unit of Measure
Specifications
Voltage Designations |
N/A 120 VAC 50/60 Hz |
Load |
N/A 30 AMPS |
Output Voltage |
N/A 0 to 97% of input voltage |
Control Signal |
N/A 4 to 20 mA at 5 volts DC, 250 Ohms |
Linearity |
N/A < 5% deviation |
Response Time |
N/A <12 mS (std unit, non soft start) |
Cooling |
N/A
Convection: 30-100 amps Fan (120VAC): 150-1200 amps |
Thermostat |
N/A 190 ºF (fan cooled units only) |
Power Dissipation (Watts) |
N/A 1.2 x maximum current |
Net Weight |
N/A 3.50 Pound |
Shipping Weight |
N/A 4 Pound |
Minimum Wire Gauge (Copper Wire Only- 90 ºC Temp Wire) |
N/A 10 AWG |
Wire Lug Torque (90 ºC Temp Wire) |
N/A 35 lb/in |
Lug Size (90 ºC Temp Wire) |
N/A 10 AWG |
Options
Soft Start |
N/A S02-2 Seconds S05-5 Seconds S10-10 Seconds S20-20 Seconds |
Current Limit |
N/A CL- Current Limit CLP-Current Limit with Panel Mount Potentiometer |
Voltage Limit |
N/A VL-Standard 1 Turn PCB VL25-25 Turn PCB |
Capabilities
Features |
N/A
|
Theory of Operation |
N/A
  The graphs below show phase angle fired voltage output on a 240V power line. The standard input signal (4-20 mA) is applied to the blue input terminal block, processed and fed to an optical coupler. The output of the optocoupler feeds the drive circuitry which is then fed to a pair of inversely connected SCR's. To obtain superior linearity, the line voltage is monitored and optically fed back to the input stage of the controller. An I²T fuse connected in series with the SCR's provides over current protection in the event of external wiring shorts, and or too large of a heater load. Additionally, a MOV (metal oxide varistor) is connected in parallel with the SCR's, providing voltage spike protection to the controller. |