Mr. Mode, you're right. We're using the SL-C range of light guards by Keyence. Both o/p types are present at the receiver connector, making it universal. Buying the appropriate cable (n or p type) connects the same colour cores to the npn or pnp ossd's -neat.
...And, reading the Standards and Regulations section in the SL-C glossy, I note that this model -even when used in conjuction with the dedicated controller- has not received certification in accordance with Article 44-2 of the Japanese H & S Law, pertaining to its use with presses and shearing machines. I find this a curious irony, given that our customer imports almost all of its test/assy equipment from Japan (CE marked), using light guards to inhibit a minimum of outputs -in one case, just the downstroke of a pressing cylinder- via the (non-safety) plc. There are no pneumatic dump valves, no isolator taps, and gaps in the "guarding" through which various limbs or small humanoids can easily pass. Funny ole world.