Converting Phemex python CCXT script from USD to USDT about ccxt

[sc0Vu]

@BingBong1234567898765321 I think you can use this symbol instead BTC/USDT:USDT.

[BingBong1234567898765321]

@BingBong1234567898765321 I think you can use this symbol instead BTC/USDT:USDT.

Hi @sc0Vu, BTC/USDT:USDT is the symbol I am using, I just mentioned BTCUSDT in the question for simplicity. I am attempting to switch from BTC/USD:USD to BTC/USDT:USDT

[ttodua]

@BingBong1234567898765321 have you tried set_margin_mode to 'cross' or 'isolated' to see if that has any effect? or set_position_mode with true (means hedged) or false (means one-way)

[BingBong1234567898765321]

@ttodua when I run:

exchange.set_margin_mode("cross", symbol = symbol)
#Note, "symbol" is predefined as "BTC/USDT:USDT"
I get this error:
Error: phemex setMarginMode() supports swap(non USDT based) contracts only

When I run:

exchange.set_position_mode(False, symbol = symbol)
It progresses further than I've been so far, so thank you! But when it gets to the section to create the limit order (code outlined above), I get this error:
Error: phemex {"code":11058,"msg":"TE_QTY_TOO_SMALL","data":null}

Is the contract size (amount) calculated differently for USDT contracts vs. USD? With the code I have above:
new_order_contract_size = round(((((usd_balance * percent_of_holdings_to_enter) * leverage) / new_order_price)*1000),1)
this code works properly for USD but seems to be giving the QTY_TOO_SMALL error with USDT. For example, my available balance being multiplied by .95 (because 100% does not allow enough room for fees) and then multiplied by leverage (ex. 20), divided by the price to place limit order at, times 1000 (I think because USD contracts are in Ep), and then rounded to the first decimal.

#Note, I have tried multiplying by 1000, 10000, and 100000 and they all get the same error.

Thank you for your support.

[BingBong1234567898765321]

@ttodua any update on this topic?

Thank you.

[BingBong1234567898765321]

Update: I discovered the solution. Since BTCUSD is settled in USD and BTCUSDT is settled in BTC and the notation is different, the below contract size formula has fixed the issue:

new_order_contract_size = round((((((usd_balance * percent_of_holdings_to_enter)/new_order_price) * leverage))),5)