ABB PSR16-600-70 Compact Soft Starter, 16 A

PSR16-600-70 (order code 1SFA896107R7000) gives a motor of up to 16 A a controlled voltage-ramp start and stop from one of ABB’s most compact softstarters. Starting and stopping follow an adjustable voltage ramp, reducing mechanical wear compared with direct-on-line switching. The built-in bypass closes after the ramp, so continuous running produces little heat, and only two phases are controlled. Pumps, fans, compressors and conveyors are the applications ABB lists, and the 16 A size fits 7.5 kW class motors, the top of the narrow housing size.

Related equipment is listed under motor soft starters, including the neighbouring PSR30-600-70 size.

Technical specifications

Duty limits of the PSR16

Start from the motor current on the nameplate: 16 A is the ceiling of this model, and ABB sizes duty by current rather than by kW. Under ABB’s reference conditions of 40 C, 4 x Ie and a 6 second ramp the PSR16 allows 10 starts per hour as supplied, rising to 20 with the optional fan; the figures assume 50 percent on-time. Each degree above 40 C, up to the 60 C limit, takes 0.8 percent off the rated current. For installations higher than 1000 m use the formula percent of Ie = 100 – (x – 1000)/150, where x is the altitude in metres; 4000 m is the maximum. Heavy-duty or frequent starts need the ABB selection tool or a larger frame.

ABB’s example coordination for the PSR16 uses manual motor starter MS132 (type 1, 50 kA), a 32 A gG fuse, J-type fuses up to 35 A for UL, thermal overload relay type TF42 and line contactor type AF16. The line contactor is not needed by the softstarter itself, but it is often used to open the circuit if the overload relay trips. Kits for direct connection to ABB manual motor starters are available, as is the PS-FBPA fieldbus plug adapter. For other combinations use ABB’s online coordination tool.

Housing group and installation

The PSR16 belongs to the PSR3 to PSR16 housing group, rated IP20 main circuit and control circuit, with 12 VA at 100-240 V AC control consumption and DIN rail or screw mounting. Setup uses three potentiometers for the start ramp, the stop ramp and the initial or end voltage; green LEDs show On/Ready and Run. A narrow housing saves enclosure space. Keep to the clearances in the manual when mounting units close together.

Sizes next to the PSR16

These types sit next to the PSR16 in ABB’s order list for the 100-240 V AC control versions.

Key features of the PSR16-600-70

• Two-phase controlled soft starting and soft stopping with an adjustable voltage ramp, reducing inrush current, torque shocks on couplings and belts, and water hammer in pump systems.
• Integrated bypass contacts close after the start ramp, so the semiconductors carry current only during ramping and the running heat loss stays low.
• Simple setup with three potentiometers and no software: start ramp time, stop ramp time and initial/end voltage.
• Run signal relay that can be used to switch a line contactor or report status to a PLC.
• Wide 208–600 V main voltage range and 100–240 V AC control supply in one type, which simplifies spares across sites with different networks.

Soft starter or variable speed drive?

A soft starter only controls the start and stop; the motor then runs at full speed directly on the network. If the process needs speed control for flow or pressure, a VFD is the correct choice. If the motor runs at fixed speed and the aim is to reduce mechanical stress and starting current, the PSR16 is smaller, simpler and generates no harmonic load during normal running. Note that a soft starter reduces starting current but does not give full torque at low current; high-inertia loads such as large fans may need a longer ramp or a larger size.

Operating in Oman and GCC conditions

Motor control centres in the Gulf often run hot. Because the PSR16 is derated by 0.8 percent of rated current for every degree above 40 °C, a panel at 50 °C reduces the usable current by about 8 percent. For a motor close to 16 A, either cool the panel, add the optional fan where duty requires it, or choose the PSR25. Dust ingress into IP20 devices should be controlled with filtered ventilation and a properly sealed enclosure, and terminals should be checked for tightness after the first months of service in sites with vibration, such as pump stations and compressor skids.

Typical applications

• Water transfer and booster pumps in utilities and buildings, where soft stop limits water hammer
• Cooling tower and ventilation fans in HVAC plants
• Small compressors and conveyor belts in process and logistics facilities

Commissioning checklist

1. Set the motor overload relay to the motor nameplate current; the PSR has no built-in motor overload protection.
2. Start with a short ramp and increase it only until the load accelerates smoothly.
3. Adjust the initial voltage so the motor begins to turn promptly after the start command.
4. Check the number of starts per hour against the duty figures above.

What to include in your RFQ

State the motor kW and nameplate current, the network voltage, the required control voltage (-70 for 100–240 V AC or -11 for 24 V AC/DC), the starts per hour, the panel temperature, and whether you need a connection kit to a manual motor starter, a fan or the fieldbus plug adapter.

Type code, order check and documents

PSR is the range, the number is the size, 600 the voltage class, and -70 tells you the control supply is 100-240 V AC; -11 would mean 24 V AC/DC. Please confirm the motor current, supply voltage, control voltage, starts per hour and any connection kit or fan before ordering.

The linked document is the PSR section of ABB’s softstarter catalog (1SFC132012C0201) with ordering details, technical data and circuit diagrams. Seven Star LLC (independent supplier, Muscat) quotes on request; prices and stock are not displayed here.