As someone who has worked extensively with electrical motors and controls...... you require to use a proper contactor, rated for motor use.
Electrical motors take very significant amounts of current during start up, the first half cycle current might be 20X the rated full load current. As the motor gains speed, the current drops to a value of 4X to 8X the full load current. This diminished current however may last from 1/2 seconds to a pair of seconds, depending on the load's inertia.
Because of the motor's inductive nature, there will be significant arcing when the contacts open. That is the reason, among others, that contactors have a pair of contacts in series for each pole, to ensure that current is interrupted in two places.
Second IMPORTANT EDIT: Optocouplers are not designed to drive a load directly. It is clearly spelled on every single datasheet. They are ONLY designed to drive thyristor gates. Use a small 1 amp Triac to actually drive the relay coil.
Hi,
Safety:
Since your circuit deals with dangerous high voltage you need to take care about safety. Especially clearance and creepage distances.
EMI/EMC:
I also miss a GND plane, fast decoupling capacitors and filter (capacitors).
You switch load current, maybe with fast current or voltage spikes.
Bouncing GND, supply and/or signal lines may cause malfunction.
Klaus
It's not a question of "possible" or "try". There are regulations, so it is a "must" and if it's not possible, then you must not sell your circuit.Where possible I've tried to keep them as far apart as possible.
I hear a misunderstanding. All traces on a two-layer PCB are considered external (B2 or B4 according to IPC). Also solder mask isn't considered as safe coating, hence B2. But you seem to design for 120 Vac (< 150V according to IEC 601010). In this case, the clearance and creepage is fine, at least for pollution degree 2 (only non-conductive POLLUTION occurs except that occasionally a temporary conductivity caused by condensation is expected). It might even work for 230V.I used the tables from IPC-2221B. The traces are not expected to be external.
Hi,
It's not a question of "possible" or "try". There are regulations, so it is a "must" and if it's not possible, then you must not sell your circuit.
You need to know what distances you need .... and you need to avoid hard edges.
Use RATSNEST to show the GND plane. And mind: a copper pour cut into pieces is no GND plane.
Has anyone mentioned using a solid-state-relay of the proper capacity to control the pump?
I hear a misunderstanding. All traces on a two-layer PCB are considered external (B2 or B4 according to IPC). Also solder mask isn't considered as safe coating, hence B2. But you seem to design for 120 Vac (< 150V according to IEC 601010). In this case, the clearance and creepage is fine, at least for pollution degree 2 (only non-conductive POLLUTION occurs except that occasionally a temporary conductivity caused by condensation is expected). It might even work for 230V.
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