Siemens 3PCI Series, Operation Manual

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Operation 3PCI SCR Power Controller Series Manual
3-4
s
Version 1.2 (19000325)
3 (Shutdown)
4 (Common)
TB1
Controller
K
Figure 3-5. On/Off Control with Output Disabled by Contact Closure
Calibrate the system as outlined in Section 3.3: Temperature Controller on page 3-2. Note that zero power
demand is accomplished by closing the contacts with the controller, and maximum power demand is present
when the contacts are open.
3.7. Controlling Several 3PCIs in Parallel with One Controller
Multiple control of parallel connected 3PCIs with a single controller is outlined below.
1. Connect each unit as shown in Figure 3-6. Refer to Section 3.3: Temperature Controller on page 3-2.
2. Remove the external shunt resistor
R101
on all of the units.
3. Connect the remaining units in parallel as shown in Figure 3-6.
4. Connect the appropriate impedance matching resistor (RC) for your controller across the output
terminals of the controller as shown in Figure 3-6. This will assure proper operation of all controllers.
RC is usually 250
Ω
or 500
Ω
.
5. Calibrate the system as outlined in Section 3.3: Temperature Controller on page 3-2.
TB1
Unit 1
1
2
TB1
Unit 2
1
2
TB1
Unit 3
1
2
TB1
Unit 4
1
2
TB1
Unit n
1
2
Controller RC
Figure 3-6. Controlling Several 3PCIs Connected in Parallel
∇ ∇ ∇