Current indication

I can not recomend simply connecting a lamp in series with the motor. The starting current will destroy the lamp unless it is so over rated that it wont light at the running current.

Use of a transformer wont help as the starting current is still several times the running current. Also if the lamp fails or is removed then you have in effect a current transformer with an open circuited secondary. This will produce a dangerously high voltage and burn out the transformer.

A home made unit is a possibility. Obtain a four diode, four terminal bridge rectifier. Connect the AC terminals in series with the load. Short circuit the positive and negative output terminals. Connect an MES mains rated pilot lamp holder across the AC terminals. Insert a 2.2 or 2.5 volt torch bulb. ANY current in excess of the bulb rating, and within the rating of the of rectifier, will produce a roughly constant voltage drop of about 1.5 volts and light the lamp. The voltage to the motor is reduced by about 1.5 volts. The brightness of the lamp will vary slightly according to the load, but any load over about 0.3 amps will light the lamp, and many amps will not burn out the lamp.

Alternatively fit a current sensing relay, these are available from china via ebay. The wire carrying the load current is passed through the device but without any direct connection thereto, as in a classic current transformer. An internal circuit closes an internal contact when the current reaches the threshold, which is adjustable. The contacts are mains rated at a very low current, often 0.1 A and may be used to switch a pilot lamp. These units are self powered and require no control supply.

I can not recomend simply connecting a lamp in series with the motor. The starting current will destroy the lamp unless it is so over rated that it wont light at the running current.

Use of a transformer wont help as the starting current is still several times the running current. Also if the lamp fails or is removed then you have in effect a current transformer with an open circuited secondary. This will produce a dangerously high voltage and burn out the transformer.

A home made unit is a possibility. Obtain a four diode, four terminal bridge rectifier. Connect the AC terminals in series with the load. Short circuit the positive and negative output terminals. Connect an MES mains rated pilot lamp holder across the AC terminals. Insert a 2.2 or 2.5 volt torch bulb. ANY current in excess of the bulb rating, and within the rating of the of rectifier, will produce a roughly constant voltage drop of about 1.5 volts and light the lamp. The voltage to the motor is reduced by about 1.5 volts. The brightness of the lamp will vary slightly according to the load, but any load over about 0.3 amps will light the lamp, and many amps will not burn out the lamp.

Alternatively fit a current sensing relay, these are available from china via ebay. The wire carrying the load current is passed through the device but without any direct connection thereto, as in a classic current transformer. An internal circuit closes an internal contact when the current reaches the threshold, which is adjustable. The contacts are mains rated at a very low current, often 0.1 A and may be used to switch a pilot lamp. These units are self powered and require no control supply.